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Full list of authors: Harra, Louise; Andretta, Vincenzo; Appourchaux, Thierry; Baudin, Frédéric; Bellot-Rubio, Luis; Birch, Aaron C.; Boumier, Patrick; Cameron, Robert H.; Carlsson, Matts; Corbard, Thierry; Davies, Jackie; Fazakerley, Andrew; Fineschi, Silvano; Finsterle, Wolfgang; Gizon, Laurent; Harrison, Richard; Hassler, Donald M.; Leibacher, John; Liewer, Paulett; Macdonald, Malcolm; Maksimovic, Milan; Murphy, Neil; Naletto, Giampiero; Nigro, Giuseppina; Owen, Christopher; Martínez-Pillet, Valentín; Rochus, Pierre; Romoli, Marco; Sekii, Takashi; Spadaro, Daniele; Veronig, Astrid; Schmutz, W.--This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/., A mission to view the solar poles from high helio-latitudes (above 60°) will build on the experience of Solar Orbiter as well as a long heritage of successful solar missions and instrumentation (e.g. SOHO Domingo et al. (Solar Phys. 162(1-2), 1–37 1995), STEREO Howard et al. (Space Sci. Rev. 136(1-4), 67–115 2008), Hinode Kosugi et al. (Solar Phys. 243(1), 3–17 2007), Pesnell et al. Solar Phys. 275(1–2), 3–15 2012), but will focus for the first time on the solar poles, enabling scientific investigations that cannot be done by any other mission. One of the major mysteries of the Sun is the solar cycle. The activity cycle of the Sun drives the structure and behaviour of the heliosphere and of course, the driver of space weather. In addition, solar activity and variability provides fluctuating input into the Earth climate models, and these same physical processes are applicable to stellar systems hosting exoplanets. One of the main obstructions to understanding the solar cycle, and hence all solar activity, is our current lack of understanding of the polar regions. In this White Paper, submitted to the European Space Agency in response to the Voyage 2050 call, we describe a mission concept that aims to address this fundamental issue. In parallel, we recognise that viewing the Sun from above the polar regions enables further scientific advantages, beyond those related to the solar cycle, such as unique and powerful studies of coronal mass ejection processes, from a global perspective, and studies of coronal structure and activity in polar regions. Not only will these provide important scientific advances for fundamental stellar physics research, they will feed into our understanding of impacts on the Earth and other planets’ space environment. © The Author(s) 2021., Open Access funding provided by ETH Zurich., With funding from the Spanish government through the Severo Ochoa Centre of Excellence accreditation SEV-2017-0709.

Objective To report the 10-year outcome of an inception cohort of patients with early rheumatoid arthritis (RA), the ESPOIR cohort, and predictors of outcome. Methods From 2003 to 2005, 813 patients were included if they had early arthritis ( Results In total, 521 (64.1%) RA patients were followed up for 10 years; 35 (4.3%) died, which appears to be similar to the French general population. Overall, 480 (92.1%) patients received a DMARD; 174 (33.4%) received at least one biologic DMARD, 13.6% within 2 years. At year 10, 273 (52.4%) patients were in DAS28 remission, 40.1% in sustained remission, 14.1% in drug-free remission, 39.7% in CDAI remission. Half of the patients achieved a health assessment questionnaire-disability index (HAQ-DI) < 0.5. SF-36 physical component and pain were well controlled. Structural progression was weak, with a mean change from baseline in modified Sharp score of 11.0 (17.9). Only 34 (6.5%) patients required major joint surgery. A substantial number of patients showed new comorbidities over 10 years. Positivity for anti-citrullinated peptides antibodies (ACPA) was confirmed as a robust predictor of long-term outcome. Conclusions We report a very mild 10-year outcome of a large cohort of patients with early RA diagnosed in the early 2000s, which was much better than results for a previous cohort of patients who were recruited in 1993. This current favourable outcome may be related to more intensive care for real-life patients.

We present the first measurements of Jupiter’s wind profile ever obtained with Doppler velocity measurements in the visible. Hitherto, knowledge about atmospheric dynamics has been obtained with cloud-tracking techniques, which consist of tracking visible features from images taken at different dates. However, cloud tracking indicates the motion of large cloud structures, which is an indication of the speed of iso-pressure regions, rather than the speed of the actual atmospheric particles. Doppler imaging is as challenging – motions are usually less than 100 m s − 1 – as appealing because it measures the speed of cloud particles instead of large cloud structures. Significant difference could appear in the case of atmospheric waves interfering with cloud structures. Here we present the first scientific results of a Doppler imaging spectrometer that is dedicated to giant-planet seismology and atmospheric dynamics by providing instantaneous line-of-sight-velocity maps of the planets of the solar system. The instrument has been developed in the framework of the projects JOVIAL (Jovian Oscillations through Velocity Images At several Longitudes) and JIVE in NM (Jovian Interiors from Velocimetry Experiment in New Mexico). It is a Fourier transform spectrometer with a fixed optical path difference working in the mid-visible domain, which monitors the position of solar Fraunhofer lines that are reflected in the planets’ upper atmospheres. After describing the instrument principle and the different steps of data reduction, we report measurement of the average zonal wind speed of Jupiter, as a function of latitude, from datasets obtained in 2015 and 2016 with two different telescopes, when the planet was close to its opposition. Our results are consistent between the two years. We compare the results with wind profiles obtained by cloud tracking on HST (Hubble Space Telescope) images taken at the same epoch, and identify a significant discrepancy in the North Equatorial Belt and northern part of the Equatorial Zone.

Solar analogues are important stars to study for understanding the properties of the Sun. Evolutionary modeling, combined with seismic and spectroscopic analysis, becomes a powerful method to characterize stellar intrinsic parameters, such as mass, radius, metallicity and age.However, these characteristics, relevant for other aspects of astrophysics or exoplanetary system physics for example, are difficult to obtain with a high precision and/or accuracy. The goal of this study is to characterize the two solar analogues HD42618 and HD43587, observed by CoRoT. In particular, we aim to infer precise mass, radius, and age, using evolutionary modeling constrained by spectroscopic, photometric, and seismic analysis. These stars show evidences of being older than the Sun but with a relatively large lithium abundance. We present the seismic analysis of HD42618, and the modeling of the two solar analogs HD42618 andHD43587 using the CESTAM stellar evolution code. Models were computed to reproduce the spectroscopic (effective temperature and metallicity) and seismic (mode frequencies) data,and the luminosity of the stars, based on Gaia parallaxes. We infer very similar values of mass and radius for both stars compared to the literature, within the uncertainties, and reproduce correctly the seismic constraints. For HD42618, the modeling shows it is slightly less massive and older than the Sun. For HD43587, it confirms it is more massive and older than the Sun,in agreement with previous results. The use of chemical clocks improves the reliability of our age estimates., 8 pages, 5 figures, 4 tables

International audience; We describe the performances of a novel Doppler imager, aimed to detect acoustic oscillations and atmospheric dynamics at the surface of giant planets of the Solar System in the frame of the JOVIAL (Jovian Oscillations detection by Velocity Imaging At several Longitudes) project. The first JOVIAL instrument was installed on the 188cm telescope at Okayama branch of National Astronomical Observatory of Japan (NAOJ) in April 2019. This instrument is a part of a ground based network of three identical instruments installed on telescopes around the world for continuous observations. First observations of Jupiter with the JOVIAL instrument were achieved in June 2019. We describe the instrument principle, its design and the set-up at Okayama observatory, as well as the performances reached during the first observing run. We finally provide plans for future observations with the network.

International audience; We present velocity maps of Jupiter obtained from the ground with a dedicated Doppler imaging spectrograph. It demonstrates the potential of this method to study the motion in the atmosphere of gaseous planets. It proves to be complementary to cloud-tracking to understand the atmospheric dynamics

We present the identification of very low frequency g modes in the asymptotic regime and two important parameters that have long been waited for: the core rotation rate, and the asymptotic equidistant period spacing of these g modes. The GOLF instrument on board the SOHO space observatory has provided two decades of full-disk helioseismic data. In the present study, we search for possible collective frequency modulations that are produced by periodic changes in the deep solar structure. Such modulations provide access to only very low frequency g modes, thus allowing statistical methods to take advantage of their asymptotic properties. For oscillatory periods in the range between 9 and nearly 48 hours, almost 100 g modes of spherical harmonic degree 1 and more than 100 g modes of degree 2 are predicted. They are not observed individually, but when combined, they unambiguouslyprovide their asymptotic period equidistance and rotational splittings, in excellent agreement with the requirements of the asymptotic approximations. Previously, p-mode helioseismology allowed the g-mode period equidistance parameter $P_0$ to be bracketed inside a narrow range, between approximately 34 and 35 minutes. Here, $P_0$ is measured to be 34 min 01 s, with a 1 s uncertainty. The previously unknown g-mode splittings have now been measured from a non-synodic reference with very high accuracy, and they imply a mean weighted rotation of 1277 $\pm$ 10 nHz (9-day period) of their kernels, resulting in a rapid rotation frequency of 1644 $\pm$ 23 nHz (period of one week) of the solar core itself, which is a factor 3.8 $\pm$ 0.1 faster than the rotation of the radiative envelope. The g modes are known to be the keys to a better understanding of the structure and dynamics of the solar core. Their detection with these precise parameters will certainly stimulate a new era of research in this field., 17 pages, 35 figures

We report here on our search for excess power in photometry of Neptune collected by the K2 mission that may be due to intrinsic global oscillations of the planet Neptune. To conduct this search, we developed new methods to correct for instrumental effects such as intrapixel variability and gain variations. We then extracted and analyzed the time-series photometry of Neptune from 49 days of nearly continuous broadband photometry of the planet. We find no evidence of global oscillations and place an upper limit of $\sim$5 ppm at 1000 \uhz\ for the detection of a coherent signal. With an observed cadence of 1-minute and point-to-point scatter less than 0.01\%, the photometric signal is dominated by reflected light from the Sun, which is in turn modulated by atmospheric variability of Neptune at the 2\% level. A change in flux is also observed due to the increasing distance between Neptune and the K2 spacecraft, and solar variability with convection-driven solar p modes present., Comment: 31 pages, 6 figure, accepted for publication in AJ

Objective To assess the ability of ultrasonography (US) to predict radiographic damage in early arthritis. Methods ESPOIR is a multicentric cohort of early arthritis (i.e., ≥2 swollen joints between 6 weeks and 6 months). US synovitis in B mode, power Doppler (PD) mode, and erosions were searched on the second through the fifth metacarpophalangeal and fifth metatarsophalangeal joints according to Outcome Measures in Rheumatology definitions. Structural radiographic progression was assessed using the modified Sharp/van der Heijde erosion score (SHS) at baseline and 1 and 2 years. Predictive factors of erosive arthritis at 2 years and rapid radiographic progression (RRP) at 1 year (defined by change of SHS ≥5) were searched. Results A total of 127 patients were included, with a mean ± SD Disease Activity Score in 28 joints of 5.1 ± 1.3; 37.6% were anti–citrullinated protein antibody positive and 27.6% had typical rheumatoid arthritis (RA) erosions on radiographs. At 2 years, 42 patients (39.2%) had typical RA erosions. US erosions predicted radiographic evidence of erosive arthritis (odds ratio [OR] 1.44, 95% confidence interval [95% CI] 1.04–1.98). PD synovitis score was predictive of RRP at 1 year (OR 1.22, 95% CI 1.04–1.42). US erosions and PD synovitis scores were associated with change of SHS on linear regression. Of the 1,184 analyzed joints, 105 (8.9%) had radiographic erosion at 1 year. At the joint level, baseline US erosions were predictive of the presence of radiographic erosions at 1 year (P < 0.001). The same trend was observed in the joints without radiographic erosions at baseline (P = 0.052). Conclusion US is useful to evaluate the potential severity of early arthritis: US erosions and PD-positive synovitis have prognostic value to predict future radiographic damage.

International audience; Context: The estimate of solar-like oscillation properties, such as their frequencies, amplitudes and lifetimes, is challenging because of their low amplitudes and will benefit from long and uninterrupted observing runs. The space telescope CoRoT allows us to obtain high-performance photometric data over a long and quasi continuous period. Among its main targets are stars for which we expect solar-like oscillations. Aims: HD 181420, an F2 main sequence star, has been observed by CoRoT during its first long run covering about 156 days. With this unprecedently high-quality set of data, our aim is to derive the p-mode parameters that can be used to probe the stellar interior. Methods: The CoRoT data obtained on HD 181420 is analysed using a classical Fourier approach for the search for the p mode signature. The p-mode parameters are then derived using global fitting of the power spectrum by a Lorentzian model, as used widely in the solar case. Results: From the p-mode frequencies, the mean value of the large spacing is estimated to be 75 {mu Hz}. The p-mode amplitudes are slightly less than 4 ppm with a line width of about 8 {mu Hz} at the maximum of the p modes. The inclination angle is estimated to be around 45 °. The large mode line-width combined with the observed mode spacing make it difficult to identify the l=2 modes and to estimate the rotational splitting. We explore two scenarios for the identification of the modes.

We report on the results of the latest solarFLAG hare-and-hounds exercise, which was concerned with testing methods for extraction of frequencies of low-degree solar p modes from data collected by Sun-as-a-star observations. We have used the new solarFLAG simulator, which includes the effects of correlated mode excitation and correlations with background noise, to make artificial timeseries data that mimic Doppler velocity observations of the Sun as a star. The correlations give rise to asymmetry of mode peaks in the frequency power spectrum. Ten members of the group (the hounds) applied their ``peak bagging'' codes to a 3456-day dataset, and the estimated mode frequencies were returned to the hare (who was WJC) for comparison. Analysis of the results reveals a systematic bias in the estimated frequencies of modes above approximately 1.8 mHz. The bias is negative, meaning the estimated frequencies systematically underestimate the input frequencies. We identify two sources that are the dominant contributions to the frequency bias. Both sources involve failure to model accurately subtle aspects of the observed power spectral density in the part (window) of the frequency power spectrum that is being fitted. One source of bias arises from a failure to account for the power spectral density coming from all those modes whose frequencies lie outside the fitting windows. The other source arises from a failure to account for the power spectral density of the weak l=4 and 5 modes, which are often ignored in Sun-as-a-star analysis. The Sun-as-a-star peak-bagging codes need to allow for both sources, otherwise the frequencies are likely to be biased.

Photometry of Procyon obtained by the MOST satellite in 2004 has been searched for p modes by several groups, with sometimes contradictory interpretations. We explore two possible factors that complicate the analysis and may lead to erroneous reports of p modes in these data. Two methods are used to illustrate the role of subtle instrumental effects in the photometry: time-frequency analysis, and a search for regularly spaced peaks in a Fourier spectrum based on the echelle diagramme approach. We find no convincing evidence of a p-mode signal in the MOST Procyon data. We can account for an apparent excess of power close to the p-mode frequency range and signs of structure in an echelle diagramme in terms of instrumental effects., Article accepted, to appear in A&A

To investigate the involvement of angiogenesis markers in very early arthritis patients and their relevance to predict further joint destruction.Levels of Vascular Endothelial Growth Factor (VEGF), angiopoietin-1 (Ang-1), and soluble Fms-like tyrosine kinase-1 (sFlt-1) were measured by ELISA in serum samples from 310 patients having polyarthritis, evolving for less than 6 months (VErA cohort). Each angiogenesis marker was measured at baseline and one year later. X-rays of hands and feet were carried out at inclusion and after 1 year and read using the van der Heidje-modified Sharp method.At baseline and after 1 year, VEGF levels were correlated with clinical and biological parameters of inflammation. We also observed a positive correlation between sFlt-1 levels and biological inflammation (Erythrocyte Sedimentation Rate (ESR): r=0.17, p=0.006; C Reactive Protein: r=0.14, p=0.02). Angiopoietin-1 levels were correlated with ESR (r=0.12, p=0.04). Interestingly, only VEGF levels measured at baseline were correlated with Disease Activity Score measured 1 year later. Relationship between angiogenesis markers and radiographic progression was also evaluated. VEGF and Ang-1 levels measured at inclusion were related with Sharp score after one year (VEGF: r=0.21, p0.001; Ang-1: r=0.24, p0.001; Spearman's test). Moreover, VEGF levels were higher in patients with radiographic progression (p=0.002).Serum concentrations of VEGF, sFlt-1 and angiopoietin-1 were correlated to parameters of inflammation and to bone destruction in early arthritis. These results contribute to demonstrate that angiogenesis reflects disease severity and angiogenesis markers might become a new useful tool to evaluate disease activity and to estimate outcome for patients with inflammatory arthritis.

Aims. Long-lived stellar oscillation modes are usually detected using Fourier transforms of time series of stellar radial velocities or brightness. It is commonly thought that one could use the cross spectrum of the two signals, or alternatively use the interleaved series of a single signal, to considerably improve the detection level by reducing the noise level. Methods. We use a statistical analysis of the cross spectrum to compute its mean value and rms value, and use the associated signal-to-noise ratio for stochastically excited modes. Results. Here, we demonstrate that the gain in the signal-to-noise ratio can indeed be improved for modes with a shorter lifetime than the observation time, but not those with a longer lifetime than the observation time.

International audience; The equator-to-pole radius difference (Δr=R eq−R pol) is a fundamental property of our star, and understanding it will enrich future solar and stellar dynamical models. The solar oblateness (Δ⊙) corresponds to the excess ratio of the equatorial solar radius (R eq) to the polar radius (R pol), which is of great interest for those working in relativity and different areas of solar physics. Δr is known to be a rather small quantity, where a positive value of about 8 milli-arcseconds (mas) is suggested by previous measurements and predictions. The Picard space mission aimed to measure Δr with a precision better than 0.5 mas. The Solar Diameter Imager and Surface Mapper (SODISM) onboard Picard was a Ritchey–Chrétien telescope that took images of the Sun at several wavelengths. The SODISM measurements of the solar shape were obtained during special roll maneuvers of the spacecraft by 30° steps. They have produced precise determinations of the solar oblateness at 782.2 nm. After correcting measurements for optical distortion and for instrument temperature trend, we found a solar equator-to-pole radius difference at 782.2 nm of 7.9±0.3 mas (5.7±0.2 km) at one σ. This measurement has been repeated several times during the first year of the space-borne observations, and we have not observed any correlation between oblateness and total solar irradiance variations.

International audience; Acoustic rates of excitation of solar p modes can be estimated from observations in order to place constraints on the modelling of the excitation process and the layers where it occurs in the star. For several reasons (including a poor signal to noise ratio and mode overlap), this estimation is difficult. In this work, we use three completely independent datasets to obtain robust estimates in the solar case for l=1 modes. We also show that the height in the solar atmosphere where the modes are observed must be taken into account. Our three sets of results are shown to be consistent, particularly in the lower part of the p-mode spectrum (from 1.8 mHz to 2.8 mHz). At higher frequencies, the agreement is not as good, because of a larger dispersion of the measurements and also because of some systematic differences which might be due to observation height estimation or to a systematic influence of the noise.

The predominant contribution to the frequency splitting of low-l solar p modes arises from the rotation of the solar interior and this lifts the frequency degeneracy in l to give a symmetric pattern where the observed (synodic) separation between adjacent m (i.e. for \Deltam\=1) is similar to400 nHz. Magnetic fields can also contribute to the splitting, but they do so in such a way as to introduce asymmetries in the arrangement of the components within each multiplet. In disc-integrated data this effect may become apparent when lgreater than or equal to2. Here, we attempt to extract estimates of the frequency asymmetries at l=2 from the analysis of disc-integrated data collected by the ground-based Birmingham Solar Oscillations Network (BiSON) and the GOLF instrument on board the ESA/NASA SOHO satellite. Our analyses demonstrate that we have evidence for there being non-zero asymmetries present (significance approximate to3-4sigma) during an epoch coincident with high levels of surface activity close to the maximum of solar cycle 23. The asymmetries are indistinguishable from zero at minimum levels of activity near the cycle 22/23 boundary. We also compare the observed asymmetries with those calculated from a model that is based upon the recent predictions of Moreno-Insertis & Solanki. While the level of agreement between the two is found to be reasonable, the observations suggest (though with poor constraints placed upon this) that the influence on the mode frequencies of high-latitude activity may not be as strong as in the model.

With over 5 years of GOLF data having some 90% continuity, a new attempt has been made to search for possible solarg modes. Statistical methods are used, based on the minimum of assumptions regarding the solar physics; namely that mode line-widths are small compared with the inverse of the observing time, and that modes are sought in the frequency interval 150 to 400Hz. A number of simulations are carried out in order to understand the expected behaviour of a system consisting principally of a solar noise continuum overlaid with some weak sharp resonances. The method adopted is based on the FFT analysis of a time series with zero-padding by a factor of 5. One prominent resonance at 284.666Hz coincides with a previous tentative assignment as one member of an n = 1, l = 1, p-mode multiplet. Components of two multiplets, previously tentatively identified as possibleg-mode candidates from the GOLF data in 1998, continue to be found, although their statistical significance is shown to be insucient, within the present assumption regarding the nature of the signal. An upper limit to the amplitude of anyg mode present is calculated using two dierent statistical approaches, according to either the assumed absence (H0 hypothesis) or the assumed presence (H1 hypothesis) of a signal. The former yields a slightly lower limit of around 6 mm/s.

Accelerated atherosclerosis has emerged as a critical issue in rheumatoid arthritis (RA). There is a need to better understand the link between RA and atherosclerosis. Our aim was to identify parameters associated with the development of subclinical atheroma in a very early arthritis (VErA) cohort.VErA-cohort patients were prospectively recruited from 1998 to 2002. Arthritis treatment was standardised from onset. The clinical, biological and radiological parameters of all patients were collected from inclusion. Carotid intima-media thickness (cIMT) was measured 7 years after their first symptoms.Among 105 patients included, 82 developed RA (mean age at onset: 51.7±12.8 years). Mean carotid artery IMT at year 7 was 0.67±0.12 mm. Larger thickness defined by values above the median (0.66) was associated with inclusion age (p10-6), swollen joint count (p=0.01), DAS44 (p=0.048) and hypertension (p=0.006). In contrast, anti-CCP positivity (50 UA/ml) was associated with thinner cIMT (p=0.03). Baseline as well as cumulated values of markers reflecting systemic inflammation, lymphocyte activation, endothelial dysfunction and oxidative stress were not correlated with carotid subclinical atherosclerosis. Major independent atheroma risk factors retained by multivariate analyses were hypertension (OR 4.33 [1.59-11.73]; p=0.004) and swollen joint count at inclusion (OR 3.87 [1.54-9.72]; p=0.004), while methotrexate use was a protective marker (OR 0.27 [0.11-0.71]; p=0.007).This study conducted from the VErA vascular cohort of community-cases of RA confirm that cIMT is under the influence of classical CV risk (hypertension), disease marker (SJC) and methotrexate intake.

International audience; PICARD is a mission dedicated to the simultaneous measurements of the solar total and spectral irradiances, its diameter and asphericity. It also probes seismically the solar interior by analysing its local intensity variation. PICARD contains a double program with in-space and on-ground measurements. Space observations are a priori most favourable, however, space entails also technical challenges, a harsh environment, and a finite mission lifetime. The PICARD spacecraft, launched on June 15, 2010 will retire in April 2014. On ground, the instruments are less affected by in-space degradation and maintenance is easily provided so if the atmosphere is properly monitored and taken into account, they still represent an opportunity to generate the needed long-term time-series. That is why ground measurements have been carried out since May 2011-and will be pursued after the space program. In this talk, we describe both sets of instruments, and then present our current results. In particular, we show new estimates of the absolute values of the total solar irradiance, diameter and oblateness. We also report about helioseismic studies and about the apparent absence of mid-term trend in the measurement of the diameter.

Parallels are drawn between the asymmetric resonance proles observed in global helioseismology and the Fano theory for autoionisation proles in atomic spectroscopy. We show that the underlying physics of the interaction of a discrete resonance with a correlated continuum is common to both systems. The approximate formula normally used for tting to proles in helioseismology is essentially similar to that developed for atomic spectroscopy by Fano. We propose that the two systems are in reality equivalent. This proposition enables us to understand better which resonances in helioseismology will be correlated with each other and with which solar background \continua". We also question whether the two interacting influences of excitation sources and correlated solar background, are really separate independent processes.

During the years 1996 through 1998 the Michelson Doppler Imager (MDI) and the Global Oscillations at Low Frequency (GOLF) experiments on the Solar and Heliospheric Observatory (SOHO) mission have provided unique and nearly uninterrupted sequences of helioseismic observations. This paper describes the analysis carried out on power spectra from 759 days of calibrated disk-averaged velocity signals provided by these two experiments. The period investigated in this work is from 1996 May 25 to 1998 June 22. We report the results of frequency determination of low-degree (l ≤ 3) acoustic modes in the frequency range between 1.4 mHz and 3.7 mHz. Rotational splittings are also measured for nonradial modes up to 3.0 mHz. The power spectrum estimation of the signals is performed using classical Fourier analysis and the line-profile parameters of the modes are determined by means of a maximum likelihood method. All parameters have been estimated using both symmetrical and asymmetrical line profile-fitting formula. The line asymmetry parameter of all modes with frequency higher than 2.0 mHz is systematically negative and independent of l. This result is consistent with the fact that both MDI and GOLF data sets investigated in this paper are predominantly velocity signals, in agreement with previous results. A comparison of the results between the symmetric and asymmetric fits shows that there is a systematic shift in the frequencies for modes above 2.0 mHz. Below this frequency, the line width of the modes is very small and the time base of the data does not provide enough statistics to reveal an asymmetry. In general, the results show that frequency and rotational splitting values obtained from both the MDI and GOLF signals are in excellent agreement, and no significant differences exist between the two data sets within the accuracy of the measurements. Our results are consistent with a uniform rotation of the solar core at the rate of about 435 nHz and show only very small deviations of the core structure from the standard solar model.

An 800 day series of GOLF velocity data, with uniquely high continuity and stability, offers the best ever signal to noise ratio obtained in global Sun observations. Following meticulous efforts to provide reliable calibration, these data have been used for measurements of frequencies, line-widths and power in the p-modes, which are used for inversion to give the internal sound speed, for comparison with theoretical models. A search for g-modes is at present inconclusive, but has yielded two possible candidate frequencies. The analysis available today is regarded as preliminary and more complete methods are currently in hand. With the resumption of routine observations following the SOHO recovery, it is hoped that the data can be considerably extended, enabling changes with the solar cycle to be explored, as well as an extended g-mode search.

PICARD is a CNES micro-satellite mission due for flight by the end of 2002, named after the name of a French astronomer who first observed with consistency the solar diameter changes during the Maunder minimum in the 16th century. It consists of two instruments measuring (i) the solar diameter and differential rotation, and (ii) the total solar irradiance. These quantities are fundamental for the understanding of the solar-Terrestrial relations, e.g. the influence of the Sun on the Earth's climate, and of the internal structure of the Sun. The continuous — or nearly continuous — viewing of the Sun from an appropriate orbit, the 5 minutes sampling rate and the very low noise measurements, will allow g-modes detection and precise diameter measurements besides accurately establishing the relationship between irradiance and diameter changes. Providing an absolute measure of the solar diameter to 1 milliarcsecond, PICARD is the first step towards instruments capable of accurate and perennial measurements, for the centuries to come, of the solar-terrestrial influence. The objectives of the mission, instrument capabilities, observing modes and performances are described.

The power spectrum of more than 630 days of full-disk solar velocity data, provided by the GOLF spectrophotometer aboard the Solar and Heliospheric Observatory, has revealed the presence of modelike structure well beyond the acoustic cutoff frequency for the solar atmosphere (νac ~5.4 mHz). Similar data produced by full-disk instruments deployed in Earth-based networks (BiSON and IRIS) had not shown any peak structure above νac: this is probably due to the higher levels of noise that are inherent in Earth-based experiments. We show that the observed peak structure (νac≤ν≤7.5 mHz) can be explained by a simple two-wave interference model if the high-frequency waves are partially reflected at the back side of the Sun.

The GOLF experiment on the SOHO mission aims to study the internal structure of the Sun by measuring the spectrum of global oscillations in the frequency range 10-7 to 10-2 Hz. Here we present the results of the analysis of the first 8 months of data. Special emphasis is put into the frequency determination of the p modes, as well as the splitting in the multiplets due to rotation. For both, we show that the improvement in S/N level with respect to the ground-based networks and other experiments is essential in achieving a very low-degree frequency table with small errors ∼ 2 parts in 10-5). On the other hand, the splitting found seems to favour a solar core which does not rotate slower than its surface. The line widths do agree with theoretical expectations and other observations.

GOLF in-flight commissioning and calibration was carried out during the first four months, most of which represented the cruise phase of SOHO towards its final LI orbit. The initial performance of GOLF is shown to be within the design specification, for the entire instrument as well as for the separate sub-systems. Malfunctioning of the polarising mechanisms after 3 to 4 months operation has led to the adoption of an unplanned operating sequence in which these mechanisms are no longer used. This mode, which measures only the blue wing of the solar sodium lines, detracts little from the detection and frequency measurements of global oscillations, but does make more difficult the absolute velocity calibration, which is currently of the order of 20%. Data continuity in the new mode is extremely high and the instrument is producing exceptionally noise-free p-mode spectra. The data set is particularly well suited to the study of effects due to the excitation mechanism of the modes, leading to temporal variations in their amplitudes. The g modes have not yet been detected in this limited data set. In the present mode of operation, there are no indications of any degradation which would limit the use of GOLF for up to 6 years or more.

We report the observations of a main-sequence star, HD 42618 (Teff = 5765 K, G3V) by the space telescope CoRoT. This is the closest star to the Sun ever observed by CoRoT in term of its fundamental parameters. Using a preliminary version of CoRoT light curves of HD 42618, p modes are detected around 3.2 mHz associated to l = 0, 1 and 2 modes with a large spacing of 142 μHz. Various methods are then used to derive the mass and radius of this star (scaling relations from solar values as well as comparison between theoretical and observationnal frequencies) giving values in the range of (0.80 − 1.02)M⊙ and (0.91 − 1.01)R⊙. A preliminary analysis of l = 0 and 1 modes allows us also to study the amount of penetrative convection at the base of the convective envelope.

We present a detailed abundance study based on spectroscopic data obtained with HARPS of two solar-analogue main targets for the asteroseismology programme of the CoRoT satellite: HD 42618 and HD 43587. The atmospheric parameters and chemical composition are accurately determined through a fully differential analysis with respect to the Sun observed with the same instrumental set-up. Several sources of systematic errors largely cancel out with this approach, which allows us to narrow down the 1-sigma error bars to typically 20 K in effective temperature, 0.04 dex in surface gravity, and less than 0.05 dex in the elemental abundances. Although HD 42618 fulfils many requirements for being classified as a solar twin, its slight deficiency in metals and its possibly younger age indicate that, strictly speaking, it does not belong to this class of objects. On the other hand, HD 43587 is slightly more massive and evolved. In addition, marked differences are found in the amount of lithium present in the photospheres of these two stars, which might reveal different mixing properties in their interiors. These results will put tight constraints on the forthcoming theoretical modelling of their solar-like oscillations and contribute to increase our knowledge of the fundamental parameters and internal structure of stars similar to our Sun., Comment: Accepted for publication in A&A, 10 pages, 7 colour figures (revised version after language editing)

PICARD is a CNES micro-satellite launched in June 2010 (Thuillier at al. 2006). Its main goal is to measure the solar shape, total and spectral irradiance during the ascending phase of the activity cycle. The SODISM telescope onboard PICARD also allows us to conduct a program for helioseismology in intensity at 535.7 nm (Corbard et al. 2008). One-minute cadence low-resolution full images are available for a so-called medium-$l$ program, and high-resolution images of the limb recorded every 2 minutes are used to study mode amplification near the limb in the perspective of g-mode search. First analyses and results from these two programs are presented here., Comment: 6 pages, 6 figures, Eclipse on the Coral Sea: Cycle 24 Ascending, GONG 2012 / LWS/SDO-5 / SOHO 27, November 12 - 16, 2012, Palm Cove, Queensland. Accepted for publication in Journal of Physics Conference Series on March 1st 2013

Fatigue frequently occurs in patients with early arthritis (EA). Determinants of its severity are unknown. We aimed to identify the factors associated with fatigue in EA and changes in fatigue after 1 year of followup.The Evaluation et Suivi de Polyarthrites Indifférenciées Récentes (Assessment and Followup of Early Undifferentiated Arthritis) cohort study is a multicenter, prospective, national cohort of patients with EA. At baseline and every 6 months up to 1 year, we recorded sociodemographic, clinical, and treatment characteristics, Arthritis Impact Measurement Scales 2 Short Form (AIMS2-SF) and Short Form 36 (SF-36) scores for health-related quality of life (HRQOL), and fatigue severity by a visual analog scale (f-VAS) and the SF-36 vitality score (fatigue_SF36).We included 813 patients (77% women, mean ± SD age 48 ± 13 years). At baseline, fatigue as assessed by the f-VAS or fatigue_SF36 was independently associated with young age, female sex, low education level, smoking, increased Disease Activity Score in 28 joints (DAS28), waking up at night, Sjögren's syndrome, and worse AIMS2-SF physical, affect, and symptom scores. At 1-year followup, a favorable change in fatigue scores was associated with increased baseline AIMS2-SF physical and affect scores (better quality of life), high baseline fatigue scores, and improved 1-year AIMS2-SF affect scores. Age, sex, and change in AIMS2-SF physical score, DAS28, and hemoglobin or C-reactive protein level were inconsistently associated with change in fatigue scores. The AIMS2-SF affect score explained most of the variance in baseline fatigue score and was an important factor in 1-year change in fatigue score.Fatigue in EA is multifactorial. Its level and its course are strongly associated with HRQOL, notably the affect dimension. These results should help professionals inform patients about fatigue, explore its causes, and develop tailored interventions.

Objective Fatigue frequently occurs in patients with early arthritis (EA). Determinants of its severity are unknown. We aimed to identify the factors associated with fatigue in EA and changes in fatigue after 1 year of followup. Methods The Evaluation et Suivi de Polyarthrites Indifferenciees Recentes (Assessment and Followup of Early Undifferentiated Arthritis) cohort study is a multicenter, prospective, national cohort of patients with EA. At baseline and every 6 months up to 1 year, we recorded sociodemographic, clinical, and treatment characteristics, Arthritis Impact Measurement Scales 2 Short Form (AIMS2-SF) and Short Form 36 (SF-36) scores for health-related quality of life (HRQOL), and fatigue severity by a visual analog scale (f-VAS) and the SF-36 vitality score (fatigue_SF36). Results We included 813 patients (77% women, mean ± SD age 48 ± 13 years). At baseline, fatigue as assessed by the f-VAS or fatigue_SF36 was independently associated with young age, female sex, low education level, smoking, increased Disease Activity Score in 28 joints (DAS28), waking up at night, Sjogren's syndrome, and worse AIMS2-SF physical, affect, and symptom scores. At 1-year followup, a favorable change in fatigue scores was associated with increased baseline AIMS2-SF physical and affect scores (better quality of life), high baseline fatigue scores, and improved 1-year AIMS2-SF affect scores. Age, sex, and change in AIMS2-SF physical score, DAS28, and hemoglobin or C-reactive protein level were inconsistently associated with change in fatigue scores. The AIMS2-SF affect score explained most of the variance in baseline fatigue score and was an important factor in 1-year change in fatigue score. Conclusion Fatigue in EA is multifactorial. Its level and its course are strongly associated with HRQOL, notably the affect dimension. These results should help professionals inform patients about fatigue, explore its causes, and develop tailored interventions.

Objectives To test the performances of combining anti-CCP second generation (CCP2) with ACR 1987 classification criteria and to diagnose early RA in a community-based very early arthritis (VErA) patient cohort. Methods The VErA cohort comprised 310 patients (median age 52 years; 68.1% women; median symptom duration 4.2 months; glucocorticoid- and DMARD naive) conservatively treated during the first 2 years. At 6 years of follow-up, a three-expert committee classified the patients into three groups: RA, other classified arthritis (OCA) or unclassified arthritis (UA). We calculated the performances of the different sets, including anti-CCP2 positivity, while retaining or deleting RF and rheumatoid nodule components with ACR 1987 criteria for early RA diagnosis. Models were subjected to receiver operating characteristics curve and logistic regression analyses to try to identify relevant sets able to classify very early RA. Results At 6 years, 149 patients were diagnosed as RA and 119 as non-RA (95 OCA and 24 UA). The original ACR 1987 criteria had 77.9% sensitivity and 64.7% specificity for the RA diagnosis at 6 years. The modified set excluding rheumatoid nodules, including anti-CCP2 positivity and retaining RF performed significantly better than ACR 1987 criteria, with 79.9% sensitivity and 64.7% specificity and with a larger area under the curve. However, in the zone of interest, i.e., ≥4/7 criteria, the curves for these sets were superimposed. Conclusions Adding anti-CCP2 positivity and deleting rheumatoid nodules failed to improve the performances of ACR 1987 classification criteria for the diagnosis of early RA.

Objective To identify, in conservatively treated, very early arthritis patients, predictors of ≥1 erosion(s) at 2 years, and to construct a prediction model. Methods Community-based adults (n = 310) who had never taken disease-modifying antirheumatic drugs (DMARDs) or steroids with swelling of ≥2 joints persisting for >4 weeks and lasting

Solar flares presumably have an impact on the deepest layers of the solar atmosphere and yet the observational evidence for such an impact is scarce. Using ten years of measurements of the Na D$_{1}$ and Na D$_2$ Fraunhofer lines, measured by GOLF onboard SOHO, we show that this photospheric line is indeed affected by flares. The effect of individual flares is hidden by solar oscillations, but a statistical analysis based on conditional averaging reveals a clear signature. Although GOLF can only probe one single wavelength at a time, we show that both wings of the Na line can nevertheless be compared. The varying line asymmetry can be interpreted as an upward plasma motion from the lower solar atmosphere during the peak of the flare, followed by a downward motion., 13 pages, 7 figures

We investigate the asteroseismology of two solar-like targets as observed with the CoRoT satellite, with particular attention paid to the mode fitting. HD 181420 and HD 49933 are typical CoRoT solar-like targets (156 and 60-day runs). The low signal-to-noise ratio (SNR) of about 3-10 prevents us from unambiguously identifying the individual oscillation modes. In particular, convergence problems appear at the edges of the oscillation spectrum. HD 181420 and HD 49933 are typical CoRoT solar-like targets (156 and 60-day runs). The low signal-to-noise ratio (SNR) of about 3-10 prevents us from unambiguously identifying the individual oscillation modes. In particular, convergence problems appear at the edges of the oscillation spectrum. We apply a Bayesian approach to the analysis of these data. We compare the global fitting of the power spectra of this time series, obtained by the classical maximum likelihood (MLE) and the maximum a posteriori (MAP) estimators. We examine the impact of the choice of the priors upon the fitted parameters. We also propose to reduce the number of free parameters in the fitting, by replacing the individual estimate of mode height associated with each overtone by a continuous function of frequency (Gaussian profile). The MAP appears as a powerful tool to constrain the global fits, but it must be used carefully and only with reliable priors. The mode width of the stars increases with the frequency over all the oscillation spectrum., Comment: 10 pages, 9 figures, 2 tables

The star HD 49385 is the first G-type solar-like pulsator observed in the seismology field of the space telescope CoRoT. The satellite collected 137 days of high-precision photometric data on this star, confirming that it presents solar-like oscillations. HD 49385 was also observed in spectroscopy with the NARVAL spectrograph in January 2009. Our goal is to characterize HD 49385 using both spectroscopic and seismic data. The fundamental stellar parameters of HD 49385 are derived with the semi-automatic software VWA, and the projected rotational velocity is estimated by fitting synthetic profiles to isolated lines in the observed spectrum. A maximum likelihood estimation is used to determine the parameters of the observed p modes. We perform a global fit, in which modes are fitted simultaneously over nine radial orders, with degrees ranging from l=0 to l=3 (36 individual modes). Precise estimates of the atmospheric parameters (Teff, [M/H], log g) and of the vsini of HD 49385 are obtained. The seismic analysis of the star leads to a clear identification of the modes for degrees l=0,1,2. Around the maximum of the signal (nu=1013 microHz), some peaks are found significant and compatible with the expected characteristics of l=3 modes. Our fit yields robust estimates of the frequencies, linewidths and amplitudes of the modes. We find amplitudes of about 5.6 +/- 0.8 ppm for radial modes at the maximum of the signal. The lifetimes of the modes range from one day (at high frequency) to a bit more than two days (at low frequency). Significant peaks are found outside the identified ridges and are fitted. They are attributed to mixed modes., 13 pages, 14 figures, accepted in A&A

Context: The F8 star HD 181906 (effective temperature ~6300K) was observed for 156 days by the CoRoT satellite during the first long run in the centre direction. Analysis of the data reveals a spectrum of solar-like acoustic oscillations. However, the faintness of the target (m_v=7.65) means the signal-to-noise (S/N) in the acoustic modes is quite low, and this low S/N leads to complications in the analysis. Aims: To extract global variables of the star as well as key parameters of the p modes observed in the power spectrum of the lightcurve. Methods: The power spectrum of the lightcurve, a wavelet transform and spot fitting have been used to obtain the average rotation rate of the star and its inclination angle. Then, the autocorrelation of the power spectrum and the power spectrum of the power spectrum were used to properly determine the large separation. Finally, estimations of the mode parameters have been done by maximizing the likelihood of a global fit, where several modes were fit simultaneously. Results: We have been able to infer the mean surface rotation rate of the star (~4 microHz) with indications of the presence of surface differential rotation, the large separation of the p modes (~87 microHz), and therefore also the ridges corresponding to overtones of the acoustic modes., Comment: Paper Accepted to be published in A&A. 10 Pages, 12 figures

Context. The CoRoT short runs give us the opportunity to observe a large variety of late-type stars through their solar-like oscillations. We report observations of the star HD175726 that lasted for 27 days during the first short run of the mission. The time series reveals a high-activity signal and the power spectrum presents an excess due to solar-like oscillations with a low signal-to-noise ratio. Aims. Our aim is to identify the most efficient tools to extract as much information as possible from the power density spectrum. Methods. The most productive method appears to be the autocorrelation of the time series, calculated as the spectrum of the filtered spectrum. This method is efficient, very rapid computationally, and will be useful for the analysis of other targets, observed with CoRoT or with forthcoming missions such as Kepler and Plato. Results. The mean large separation has been measured to be 97.2+-0.5 microHz, slightly below the expected value determined from solar scaling laws.We also show strong evidence for variation of the large separation with frequency. The bolometric mode amplitude is only 1.7+-0.25 ppm for radial modes, which is 1.7 times less than expected. Due to the low signal-to-noise ratio, mode identification is not possible for the available data set of HD175726. Conclusions. This study shows the possibility of extracting a seismic signal despite a signal-to-noise ratio of only 0.37. The observation of such a target shows the efficiency of the CoRoT data, and the potential benefit of longer observing runs., Comment: 8 pages. Accepted in A&A

The space experiment CoRoT has recently detected transits by a hot Jupiter across the disc of an active G7V star (CoRoT-Exo-2a) that can be considered as a good proxy for the Sun at an age of approximately 0.5 Gyr. We present a spot modelling of the optical variability of the star during 142 days of uninterrupted observations performed by CoRoT with unprecedented photometric precision. We apply spot modelling approaches previously tested in the case of the Sun by modelling total solar irradiance variations. To model the light curve of CoRoT-Exo-2a, we take into account both the photometric effects of cool spots as well as those of solar-like faculae, adopting solar analogy. Two active longitudes initially on opposite hemispheres are found on the photosphere of CoRoT-Exo-2a with a rotation period of 4.522 $\pm$ 0.024 days. Their separation changes by approximately 80 degrees during the time span of the observations. From this variation, a relative amplitude of the surface differential rotation lower than about 1 percent is estimated. Individual spots form within the active longitudes and show an angular velocity about 1 percent smaller than that of the longitude pattern. The total spotted area shows a cyclic oscillation with a period of 28.9 $\pm$ 4.3 days, which is close to 10 times the synodic period of the planet as seen by the rotating active longitudes. The implications of such results for the internal rotation of CoRoT-Exo-2a are discussed on the basis of solar analogy. A possible magnetic star-planet interaction is suggested by the cyclic variation of the spotted area. Alternatively, the 28.9-d cycle may be related to Rossby-type waves propagating in the subphotospheric layers of the star., Comment: 9 pages, 8 figures, accepted by Astronomy and Astrophysics

Solar gravity modes (or g modes) -- oscillations of the solar interior for which buoyancy acts as the restoring force -- have the potential to provide unprecedented inference on the structure and dynamics of the solar core, inference that is not possible with the well observed acoustic modes (or p modes). The high amplitude of the g-mode eigenfunctions in the core and the evanesence of the modes in the convection zone make the modes particularly sensitive to the physical and dynamical conditions in the core. Owing to the existence of the convection zone, the g modes have very low amplitudes at photospheric levels, which makes the modes extremely hard to detect. In this paper, we review the current state of play regarding attempts to detect g modes. We review the theory of g modes, including theoretical estimation of the g-mode frequencies, amplitudes and damping rates. Then we go on to discuss the techniques that have been used to try to detect g modes. We review results in the literature, and finish by looking to the future, and the potential advances that can be made -- from both data and data-analysis perspectives -- to give unambiguous detections of individual g modes. The review ends by concluding that, at the time of writing, there is indeed a consensus amongst the authors that there is currently no undisputed detection of solar g modes., Comment: 71 pages, 18 figures, accepted by Astronomy and Astrophysics Review

International audience; Context: The first asteroseismology results from CoRoT are presented, on a star showing Sun-like oscillations. We have analyzed a 60 day lightcurve of high-quality photometric data collected by CoRoT on the F5 V star HD 49933. The data reveal a rich spectrum of overtones of low-degree p modes. Aims: Our aim was to extract robust estimates of the key parameters of the p modes observed in the power spectrum of the lightcurve. Methods: Estimation of the mode parameters was performed using maximum likelihood estimation of the power spectrum. A global fitting strategy was adopted whereby 15 mode orders of the mode spectrum (45 modes) were fitted simultaneously. Results: The parameter estimates that we list include mode frequencies, peak linewidths, mode amplitudes, and a mean rotational frequency splitting. We find that the average large frequency (overtone) spacing derived from the fitted mode frequencies is 85.9 ± 0.15 muHz. The frequency of maximum amplitude of the radial modes is at 1760 muHz, where the observed rms mode amplitude is 3.75 ± 0.23 ppm. The mean rotational splitting of the non-radial modes appears to be in the range &ap;2.7 muHz to &ap;3.4 muHz. The angle of inclination offered by the star, as determined by fits to the amplitude ratios of the modes, appears to be in the range &ap;50 degrees to &ap;62 degrees.

4 pages, 3 figures.-- Supporting Online Material: Text, Fig. S1, Table S1 and References, available at: http://www.sciencemag.org/cgi/content/full/322/5901/558/DC1, Oscillations of the Sun have been used to understand its interior structure. The extension of similar studies to more distant stars has raised many difficulties despite the strong efforts of the international community over the past decades. The CoRoT (Convection Rotation and Planetary Transits) satellite, launched in December 2006, has now measured oscillations and the stellar granulation signature in three main sequence stars that are noticeably hotter than the sun. The oscillation amplitudes are about 1.5 times as large as those in the Sun; the stellar granulation is up to three times as high. The stellar amplitudes are about 25% below the theoretic values, providing a measurement of the nonadiabaticity of the process ruling the oscillations in the outer layers of the stars.

The Global Oscillation at Low Frequencies (GOLF) experiment is a resonant scattering spectrophotometer on board the Solar and Heliospheric Observatory (SoHO) mission, originally designed to measure the disk-integrated solar oscillations of the Sun. This instrument was designed in a relative photometric mode involving both wings of the neutral sodium doublet (D1 at λ 5896 and D2 at λ 5890 A). However, a “one-wing” photometric mode has been selected to ensure 100% continuity in the measurements after a problem in the polarization mechanisms. Thus the velocity is obtained from only two points on the same wing of the lines. This operating configuration imposes tighter constraints on the stability of the instrument with a higher sensitivity to instrumental variations. In this paper we discuss the evolution of the instrument during the last 8 years in space and the corrections applied to the measured counting rates due to known instrumental effects. We also describe a scaling procedure to obtain the variation of the Doppler velocity based on our knowledge of the sodium profile slope and we compare it to previous velocity estimations.

Tumour necrosis factor (TNF)-α plays a key role in the pathogenesis of rheumatoid arthritis (RA). It binds to two receptors, namely TNF receptor (TNFR)I and TNFRII. Several studies have suggested an association between TNFRII 196R/R genotype and RA. The objective of the present study was to evaluate the predictive value of the TNFRII 196R allele for RA diagnosis and prognosis in a cohort of patients with very early arthritis. We followed up a total of 278 patients recruited from the community, who had swelling of at least two joints that had persisted for longer than 4 weeks but had been evolving for less than 6 months, and who had not received disease-modifying antirheumatic drugs or steroid therapy. At 2 years, patients were classified according to the American College of Rheumatology criteria. All patients were genotyped with respect to TNFRII 196M/R polymorphism. Radiographs of hands and feet (read according to the modified Sharp method) and the Health Assessment Questionnaire were used to quantify structural and functional severity. The cohort of 278 patients was found to include 156 and 122 RA and non-RA patients, respectively. The TNFRII 196R allele was found to be associated with RA (P = 0.002). However, progression of radiographic severity and Health Assessment Questionnaire scores over 1 year did not differ between carriers of the 196R allele and noncarriers. Our findings suggest that the TNFRII 196R allele may be associated with RA diagnosis but that it does not predict early radiographic progression or functional severity in patients with very early, unclassified arthritis.

International audience; PICARD is an investigation dedicated to the simultaneous measurement of the absolute total and spectral solar irradiance, the diameter and solar shape, and to the Sun's interior probing by the helioseismology method. The spacecraft was successfully launched into a Sun-synchronous dawn-dusk orbit on 15 June 2010 by a DNEPR-1 launcher for a life expectancy of 2 years; its operational mission ended in March, 2014.The payload consists of the SODISM imager (SOlar Diameter Imager and Surface Mapper) and of two radiometers, SOVAP (SOlar VAriability PICARD) and PREMOS (PREcision MOnitoring Sensor), which measure Total Solar Irradiance. Filter radiometers on PREMOS monitor the Solar Spectral Irradiance in six selected bands in the near UV, visible, and near IR wavelength regions. The SODISM telescope monitors continuously solar activity from the middle ultraviolet (UV) to the near infrared (IR) spectral domains.We shall give an overview of the mission, as well as the behaviour of the instruments in orbit, and the scientific results.

International audience; We present the identification of very low frequency g modes, in the asymptotic regime, and two important parameters: the core rotation rate and the asymptotic equidistant period spacing of these g modes. The GOLF instrument on the SOHO space observatory has provided two decades of full disk helioseismic data. The search for g modes in GOLF measurements has been extremely difficult, due to solar and instrumental noise. In the present study, the p modes of the GOLF signal are analyzed differently, searching for possible collective frequency modulations produced by periodic changes in the deep solar structure. Such modulations provide access to only very low frequency g modes, thus allowing statistical methods to take advantage of their asymptotic properties. For oscillatory periods in the range between 9 and nearly 48 hours, almost 100 g modes of spherical harmonic degree 1 and more than 100 g modes of degree 2 are predicted. They are not observed individually, but when combined, they unambiguously provide their asymptotic period equidistance and rotational splittings, in excellent agreement with the requirements of the asymptotic approximations. P0, the g-mode period equidistance parameter, is measured to be 34 min 01 s, with a 1 s uncertainty. The previously unknown g-mode splittings have now been measured from a non synodic reference with a very high accuracy, and they imply a mean weighted rotation of 1277 ± 10 nHz (9-day period) of their kernels, resulting in a rapid rotation frequency of 1644 ± 23 nHz (period of one week) of the solar core itself, which is a factor 3:8 ± 0:1 faster than the rotation of the radiative envelope.