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International audience; Euclid is a mission of the European Space Agency that is designed to constrain the properties of dark energy and gravity via weak gravitational lensing and galaxy clustering. It will carry out a wide area imaging and spectroscopy survey (the Euclid Wide Survey: EWS) in visible and near-infrared bands, covering approximately 15 000 deg 2 of extragalactic sky in six years. The wide-field telescope and instruments are optimised for pristine point spread function and reduced stray light, producing very crisp images. This paper presents the building of the Euclid reference survey: the sequence of pointings of EWS, deep fields, and calibration fields, as well as spacecraft movements followed by Euclid as it operates in a step-and-stare mode from its orbit around the Lagrange point L2. Each EWS pointing has four dithered frames; we simulated the dither pattern at the pixel level to analyse the effective coverage. We used up-to-date models for the sky background to define the Euclid region-of-interest (RoI). The building of the reference survey is highly constrained from calibration cadences, spacecraft constraints, and background levels; synergies with ground-based coverage were also considered. Via purposely built software, we first generated a schedule for the calibrations and deep fields observations. On a second stage, the RoI was tiled and scheduled with EWS observations, using an algorithm optimised to prioritise the best sky areas, produce a compact coverage, and ensure thermal stability. The result is the optimised reference survey RSD_2021A, which fulfils all constraints and is a good proxy for the final solution. The current EWS covers ≈14 500 deg 2 . The limiting AB magnitudes (5 σ point-like source) achieved in its footprint are estimated to be 26.2 (visible band I E ) and 24.5 (for near infrared bands Y E , J E , H E ); for spectroscopy, the H α line flux limit is 2 × 10 −16 erg −1 cm −2 s −1 at 1600 nm; and for diffuse emission, the surface brightness limits are 29.8 (visible band) and 28.4 (near infrared bands) mag arcsec −2 .

Type II collagen-induced arthritis (CIA) is an animal model of rheumatoid arthritis that has been used extensively to address questions of disease pathogenesis and to validate novel therapeutic targets. Susceptibility to CIA is strongly associated with major histocompatibility complex class II genes, and the development of arthritis is accompanied by a robust T- and B-cell response to type II collagen. The main pathological features of CIA include proliferative synovitis with infiltration of inflammatory cells, pannus formation, cartilage degradation, erosion of bone and fibrosis. Pro-inflammatory cytokines, such as tumour necrosis factor alpha and interleukin-1beta, are expressed in the arthritic joints in both murine CIA and human rheumatoid arthritis, and blockade of these molecules results in amelioration of disease. Hence, there is a great deal of interest in the development of small-molecular-weight inhibitors of pro-inflammatory cytokines. There is also interest in the development and testing of drugs with the capacity to modulate the immune pathways involved in driving the inflammatory response in arthritis. For these reasons, there is a need to monitor the effect of novel treatments on cytokine expression in vivo. In this review, we outline the various techniques used to detect cytokines in experimental arthritis and describe how these techniques have been used to quantify changes in cytokine expression following therapeutic intervention.

Euclid is a space-based survey mission from the European Space Agency designed to understand the origin of the Universe's accelerating expansion. It will use cosmological probes to investigate the nature of dark energy, dark matter and gravity by tracking their observational signatures on the geometry of the universe and on the cosmic history of structure formation. The mission is optimised for two independent primary cosmological probes: Weak gravitational Lensing (WL) and Baryonic Acoustic Oscillations (BAO). The Euclid payload consists of a 1.2 m Korsch telescope designed to provide a large field of view. It carries two instruments with a common field-of-view of ~0.54 deg2: the visual imager (VIS) and the near infrared instrument (NISP) which contains a slitless spectrometer and a three bands photometer. The Euclid wide survey will cover 15,000 deg2 of the extragalactic sky and is complemented by two 20 deg2 deep fields. For WL, Euclid measures the shapes of 30-40 resolved galaxies per arcmin2 in one broad visible R+I+Z band (550-920 nm). The photometric redshifts for these galaxies reach a precision of dz/(1+z) < 0.05. They are derived from three additional Euclid NIR bands (Y, J, H in the range 0.92-2.0 micron), complemented by ground based photometry in visible bands derived from public data or through engaged collaborations. The BAO are determined from a spectroscopic survey with a redshift accuracy dz/(1+z) =0.001. The slitless spectrometer, with spectral resolution ~250, predominantly detects Ha emission line galaxies. Euclid is a Medium Class mission of the ESA Cosmic Vision 2015-2025 programme, with a foreseen launch date in 2019. This report (also known as the Euclid Red Book) describes the outcome of the Phase A study.

Although it is accepted that the mantle wedge above subduction zones is oxidized, the exact processes of relative oxidation are still controversial (e.g. Parkinson & Arculus, 1999). It is widely recognized that oxidized components are transferred to the overlying mantle wedge by fluid phases coming from the subducting slab (e.g. Parkinson & Arculus, 1999; Peslier et al., 2002; Malaspina et al., 2009; Rowe et al., 2009; Hirschmann, 2009); however, the study of the redox reactions occurring at the interface between the subducting slab and the mantle wedge, is often hampered by the difficulties in accurately determining the oxidation state of phase assemblages involved in these redox reactions. In this contribution we report the results of a micro-XANES study on strongly-zoned garnet crystals from an eclogitic FeTi-oxide gabbro (Monviso meta-ophiolites, western Alps), aimed to the determination of the Fe3+/ΣFe variation across the crystals. The studied sample extraordinarily well preserves evidence of its prograde evolution during subduction down to a depth of ca. 80 km (Groppo & Castelli, 2010). Because in the studied garnet the Fe3+/ΣFe variations are small and occur on a micrometric scale, the challenge of this study was twofold: (i) the spatial resolution must be of the order of microns, and (ii) the spectral resolution must be as small as possible in order to appreciate the differences in the oxidation state of garnet. The results of the XANES spectra, acquired with a spatial resolution of 1.7 μm × 5.3 μm, show that the Fe3+/ΣFe ratio decreases from a maximum of 0.14 in the garnet core to a minimum of 0.00 in the garnet rim. These results are in excellent agreement with those previously obtained using the “flank method” at the electron microprobe. Comparing the results obtained with the two techniques, it can be concluded that micro-XANES can be successfully used to estimate Fe3+/ΣFe variations in natural garnets at a high spatial resolution (≤ 5 μm), provided that the differences in Fe3+/ΣFe are higher than ca. 5%. The “flank method” is the only method which has demonstrated, so far, to be sensitive to smaller variations (i.e. < 5%) of the Fe3+/ΣFe ratio in garnet, for ΣFe > 8 wt%. The measured Fe3+/ΣFe zoning in garnet, combined with the already estimated P-T conditions of its growth, provides qualitative information about the redox equilibria occurring during subduction of the studied FeTi-oxide metagabbro. Dehydration-redox equilibria involving the breakdown of lawsonite and chlorite (i.e. Qtz+Lws+Chlss+Omp1ss+Grt1ss=Grt2ss+Omp2ss+H2O+O2) are responsible for a significant chemical re-equilibration of garnet (and omphacite), resulting in a progressive decrease of its Fe3+/ΣFe ratio toward the rim and, consequently, in the release of oxygen. Dehydration-redox reactions of this type, occurring at least locally during subduction of the oceanic crust, may be likely involved in the oxidation of the mantle wedge. References Groppo C. & Castelli D. (2010). J. Petrol. 51, 2489-2514. Hirschmann M.M. (2009). Science 325, 545-546. Malaspina N., Poli S. & Fumagalli P. (2009). J. Petrol. 50, 1533-1552. Parkinson I.J. & Arculus R.J. (1999). Chem. Geol. 160, 409-423. Peslier A.H., Luhr J.F. & Post J. (2002). Earth Planet. Sci. Lett. 201, 69-86. Rowe M.C., Kent A.J.R. & Nielsen R.L. (2009). J. Petrol. 50, 61-91.

Opitz (or G/BBB) syndrome is a pleiotropic genetic disorder characterized by hypertelorism, hypospadias, and additional midline defects. This syndrome is heterogeneous with an X-linked (XLOS) and an autosomal dominant (ADOS) form. The gene implicated in the XLOS form, MID1, encodes a protein containing a RING-Bbox-Coiled-coil motif belonging to the tripartite motif (TRIM) family. To further clarify the molecular basis of XLOS, we have undertaken mutation analysis of the MID1 gene in patients with Opitz syndrome (OS). We found novel mutations in 11 of 63 male individuals referred to us as sporadic or familial X-linked OS cases. The mutations are scattered throughout the gene, although more are represented in the 3' region. By reviewing all the MID1-mutated OS patients so far described, we confirmed that hypertelorism and hypospadias are the most frequent manifestations, being present in almost every XLOS individual. However, it is clear that laryngo-tracheo-esophageal (LTE) defects are also common anomalies, being manifested by all MID1-mutated male patients. Congenital heart and anal abnormalities are less frequent than reported in literature. In addition, we can include limb defects in the OS clinical synopsis as we found a MID1-mutated patient showing syndactyly. The low frequency of mutations in MID1 and the high variability of the phenotype suggest the involvement of other genes in the OS phenotype.

Euclid is an ESA Cosmic-Vision wide-field-space mission which is designed to explain the origin of the acceleration of Universe expansion. The mission will investigate at the same time two primary cosmological probes: Weak gravitational Lensing (WL) and Galaxy Clustering (in particular Baryon Acoustic Oscillations, BAO). The extreme precision requested on primary science objectives can only be achieved by observing a large number of galaxies distributed over the whole sky in order to probe the distribution of dark matter and galaxies at all scales. The extreme accuracy needed requires observation from space to limit all observational biases in the measurements. The definition of the Euclid survey, aiming at detecting billions of galaxies over 15 000 square degrees of the extragalactic sky, is a key parameter of the mission. It drives its scientific potential, its duration and the mass of the spacecraft. The construction of a Reference Survey derives from the high level science requirements for a Wide and a Deep survey. The definition of a main sequence of observations and the associated calibrations were indeed a major achievement of the Definition Phase. Implementation of this sequence demonstrated the feasibility of covering the requested area in less than 6 years while taking into account the overheads of space segment observing and maneuvering sequence. This reference mission will be used for sizing the spacecraft consumables needed for primary science. It will also set the framework for optimizing the time on the sky to fulfill the primary science and maximize the Euclid legacy.

Euclid is a space-borne sky survey mission designed to understand the origin of the Universe's accelerating expansion. The mission is optimised for two independent cosmological probes: weak gravitational lensing and galaxy clustering. The payload consists of a 1.2 m Korsch telescope with two instruments: a visual imager (VIS) and a near-infrared spectrometer-photometer (NISP). Both instruments cover a large common field of view of 0.54 deg2, enabling a sky survey of at least 15,000 deg2. A status overview of the mission is presented: the scientific objectives, payload, satellite, and science operations. Euclid's launch is foreseen in 2019.