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| 2. |
- Cirasuolo, M., et al.
(författare)
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MOONS: the Multi-Object Optical and Near-infrared Spectrograph for the VLT
- 2014
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Ingår i: Ground-based and Airborne Instrumentation for Astronomy V. - : SPIE. - 1996-756X .- 0277-786X. ; 9147, s. 91470-91470
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Konferensbidrag (refereegranskat)abstract
- MOONS (the Multi-Object Optical and Near-infrared Spectrograph) has been selected by ESO as a third-generation instrument for the Very Large Telescope (VLT). The light grasp of the large collecting area offered by the VLT (8.2m diameter), combined with the large multiplex and wavelength coverage (optical to near-IR: 0.8 -1.8 mu m) of MOONS will provide the European astronomical community with a powerful, unique instrument able to pioneer a wide range of Galactic, extragalactic and cosmological studies, and it will provide crucial follow-up for major facilities such as Gaia, VISTA, Euclid and LSST. MOONS has the observational power needed to unveil galaxy formation and evolution over the entire history of the Universe, from stars in our Milky Way, through the redshift desert, and up to the epoch of very first galaxies and reionization of the Universe at redshifts of z > 8-9, just a few million years after the Big Bang. From five years of observations MOONS will provide high-quality spectra for > 3M stars in our Galaxy and the Local Group, and for 1-2M galaxies at z > 1 (for an SDSS-like survey), promising to revolutionize our understanding of the Universe. The baseline design consists of similar to 1000 fibres, deployable over a field-of-view of similar to 500 arcmin(2), the largest patrol field offered by the Nasmyth focus at the VLT. The total wavelength coverage is 0.8 -1.8 mu m with two spectral resolving powers: in the medium-resolution mode (R similar to 4,000-6,000) the entire wavelength range is observed simultaneously, while the high-resolution mode will cover three selected sub-regions simultaneously: one region with R similar to 8,000 near the Ca II triplet to measure stellar radial velocities, and two regions at R similar to 20,000 (one in each of the J- and H-bands), for precision measurements of chemical abundances.
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| 3. |
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| 4. |
- Zerbi, F. M., et al.
(författare)
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HIRES : The High Resolution Spectrograph for E-ELT
- 2014
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Ingår i: Ground-based and Airborne Instrumentation for Astronomy V. - : SPIE. - 9780819496157
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Konferensbidrag (refereegranskat)abstract
- The current instrumentation plan for the E-ELT foresees a High Resolution Spectrograph conventionally indicated as HIRES. Shaped on the study of extra-solar planet atmospheres, Pop-III stars and fundamental physical constants, HIRES is intended to embed observing modes at high-resolution (up to R=150000) and large spectral range (from the blue limit to the K band) useful for a large suite of science cases that can exclusively be tackled by the E-ELT. We present in this paper the solution for HIRES envisaged by the "HIRES initiative", the international collaboration established in 2013 to pursue a HIRES on E-ELT.
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| 5. |
- Cabral, R.A., et al.
(författare)
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Volatile cycling of H2O, CO2, F, and Cl in the HIMU mantle: A new window provided by melt inclusions from oceanic hotspot lavas at Mangaia, Cook Islands.
- 2014
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Ingår i: Geochemistry Geophysics Geosystems. - 1525-2027. ; 15, s. 4445-4467
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Tidskriftsartikel (refereegranskat)abstract
- Mangaia hosts the most radiogenic Pb-isotopic compositions observed in ocean island basalts and represents the HIMU (high µ = 238U/204Pb) mantle end-member, thought to result from recycled oceanic crust. Complete geochemical characterization of the HIMU mantle end-member has been inhibited due to a lack of deep submarine glass samples from HIMU localities. We homogenized olivine-hosted melt inclusions separated from Mangaia lavas and the resulting glassy inclusions made possible the first volatile abundances to be obtained from the HIMU mantle end-member. We also report major and trace element abundances and Pb-isotopic ratios on the inclusions, which have HIMU isotopic fingerprints. We evaluate the samples for processes that could modify the volatile and trace element abundances postmantle melting, including diffusive Fe and H2O loss, degassing, and assimilation. H2O/Ce ratios vary from 119 to 245 in the most pristine Mangaia inclusions; excluding an inclusion that shows evidence for assimilation, the primary magmatic H2O/Ce ratios vary up to ∼200, and are consistent with significant dehydration of oceanic crust during subduction and long-term storage in the mantle. CO2 concentrations range up to 2346 ppm CO2 in the inclusions. Relatively high CO2 in the inclusions, combined with previous observations of carbonate blebs in other Mangaia melt inclusions, highlight the importance of CO2 for the generation of the HIMU mantle. F/Nd ratios in the inclusions (30 ± 9; 2σ standard deviation) are higher than the canonical ratio observed in oceanic lavas, and Cl/K ratios (0.079 ± 0.028) fall in the range of pristine mantle (0.02–0.08).
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| 6. |
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| 7. |
- Cabral, Rita A., et al.
(författare)
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Anomalous sulphur isotopes in plume lavas reveal deep mantle storage of Archaean crust
- 2013
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 496:7446, s. 490-494
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Tidskriftsartikel (refereegranskat)abstract
- Basaltic lavas erupted at some oceanic intraplate hotspot volcanoes are thought to sample ancient subducted crustal materials(1,2). However, the residence time of these subducted materials in the mantle is uncertain and model-dependent(3), and compelling evidence for their return to the surface in regions of mantle upwelling beneath hotspots is lacking. Here we report anomalous sulphur isotope signatures indicating mass-independent fractionation (MIF) in olivine-hosted sulphides from 20-million-year-old ocean island basalts from Mangaia, Cook Islands (Polynesia), which have been suggested to sample recycled oceanic crust(3,4). Terrestrial MIF sulphur isotope signatures (in which the amount of fractionation does not scale in proportion with the difference in the masses of the isotopes) were generated exclusively through atmospheric photochemical reactions until about 2.45 billion years ago(5-7). Therefore, the discovery of MIF sulphur in these young plume lavas suggests that sulphur-probably derived from hydrothermally altered oceanic crust-was subducted into the mantle before 2.45 billion years ago and recycled into the mantle source of Mangaia lavas. These new data provide evidence for ancient materials, with negative Delta S-33 values, in the mantle source for Mangaia lavas. Our data also complement evidence for recycling of the sulphur content of ancient sedimentary materials to the subcontinental lithospheric mantle that has been identified in diamond-hosted sulphide inclusions(8,9). This Archaean age for recycled oceanic crust also provides key constraints on the length of time that subducted crustal material can survive in the mantle, and on the timescales of mantle convection from subduction to upwelling beneath hotspots.
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| 9. |
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| 10. |
- Sundqvist, Martina, et al.
(författare)
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Increased intracellular oxygen radical production in neutrophils during febrile episodes of PFAPA syndrome.
- 2013
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Ingår i: Arthritis and rheumatism. - : Wiley. - 1529-0131 .- 0004-3591. ; 65:11, s. 2971-2983
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Tidskriftsartikel (refereegranskat)abstract
- Objective: Periodic Fever, Aphthous stomatitis, Pharyngitis, and cervical Adenitis (PFAPA) syndrome is an autoinflammatory disease of unknown etiology that primarily affects preschool children. PFAPA is characterized by recurrent attacks of fever and inflammatory symptoms consistent with the disease acronym. Since autoinflammatory diseases by definition are mediated by cells of the innate immune system, we aimed at evaluating functional features of neutrophils, the most abundant innate immune cell in circulation, in PFAPA syndrome. Methods: Blood neutrophils, obtained from PFAPA patients during both febrile and asymptomatic afebrile phases of disease, as well as from healthy children (afebrile controls) and children with fever and abdominal pain (febrile controls) were analysed for three key neutrophil characteristics: (i) apoptosis (measured by Annexin V/7AAD staining), (ii) production of reactive oxygen species (ROS; by luminol/isoluminol-amplified chemiluminescence), and (iii) priming status (as responsiveness to galectin-3 and upregulation of CD11b). Results: Compared to neutrophils from both PFAPA patients in an afebrile interval and from febrile controls, neutrophils obtained during a PFAPA flare produced elevated levels of intracellular NADPH-oxidase-derived ROS, had significantly diminished rates of spontaneous apoptosis, and displayed signatures of priming. In contrast, neutrophils from afebrile PFAPA patients had a significantly elevated rate of spontaneous apoptosis compared to neutrophils from afebrile controls. Conclusions: We demonstrate that three key aspects of neutrophil innate immune function, namely apoptosis, priming, and generation of an intracellular oxidative burst are altered, most prominently during febrile attacks in PFAPA syndrome. © 2013 American College of Rheumatology.
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