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| 2. |
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| 3. |
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| 4. |
- Abadie, J., et al.
(författare)
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Implementation and testing of the first prompt search for gravitational wave transients with electromagnetic counterparts
- 2012
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Ingår i: Astronomy & Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 539
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Tidskriftsartikel (refereegranskat)abstract
- Aims. A transient astrophysical event observed in both gravitational wave (GW) and electromagnetic (EM) channels would yield rich scientific rewards. A first program initiating EM follow-ups to possible transient GW events has been developed and exercised by the LIGO and Virgo community in association with several partners. In this paper, we describe and evaluate the methods used to promptly identify and localize GW event candidates and to request images of targeted sky locations. Methods. During two observing periods (Dec. 17, 2009 to Jan. 8, 2010 and Sep. 2 to Oct. 20, 2010), a low-latency analysis pipeline was used to identify GW event candidates and to reconstruct maps of possible sky locations. A catalog of nearby galaxies and Milky Way globular clusters was used to select the most promising sky positions to be imaged, and this directional information was delivered to EM observatories with time lags of about thirty minutes. A Monte Carlo simulation has been used to evaluate the low-latency GW pipeline's ability to reconstruct source positions correctly. Results. For signals near the detection threshold, our low-latency algorithms often localized simulated GW burst signals to tens of square degrees, while neutron star/neutron star inspirals and neutron star/black hole inspirals were localized to a few hundred square degrees. Localization precision improves for moderately stronger signals. The correct sky location of signals well above threshold and originating from nearby galaxies may be observed with similar to 50% or better probability with a few pointings of wide-field telescopes.
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| 5. |
- Andreoni, I., et al.
(författare)
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Follow Up of GW170817 and Its Electromagnetic Counterpart by Australian-Led Observing Programmes
- 2017
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Ingår i: Publications Astronomical Society of Australia. - : Cambridge University Press (CUP). - 1323-3580 .- 1448-6083. ; 34
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Forskningsöversikt (refereegranskat)abstract
- The discovery of the first electromagnetic counterpart to a gravitational wave signal has generated follow-up observations by over 50 facilities world-wide, ushering in the new era of multi-messenger astronomy. In this paper, we present follow-up observations of the gravitational wave event GW170817 and its electromagnetic counterpart SSS17a/DLT17ck (IAU label AT2017gfo) by 14 Australian telescopes and partner observatories as part of Australian-based and Australian-led research programs. We report early- to late-time multi-wavelength observations, including optical imaging and spectroscopy, mid-infrared imaging, radio imaging, and searches for fast radio bursts. Our optical spectra reveal that the transient source emission cooled from approximately 6 400 K to 2 100 K over a 7-d period and produced no significant optical emission lines. The spectral profiles, cooling rate, and photometric light curves are consistent with the expected outburst and subsequent processes of a binary neutron star merger. Star formation in the host galaxy probably ceased at least a Gyr ago, although there is evidence for a galaxy merger. Binary pulsars with short (100 Myr) decay times are therefore unlikely progenitors, but pulsars like PSR B1534+12 with its 2.7 Gyr coalescence time could produce such a merger. The displacement (similar to 2.2 kpc) of the binary star system from the centre of the main galaxy is not unusual for stars in the host galaxy or stars originating in the merging galaxy, and therefore any constraints on the kick velocity imparted to the progenitor are poor.
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| 6. |
- Kattge, Jens, et al.
(författare)
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TRY plant trait database - enhanced coverage and open access
- 2020
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Ingår i: Global Change Biology. - : Wiley-Blackwell. - 1354-1013 .- 1365-2486. ; 26:1, s. 119-188
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Tidskriftsartikel (refereegranskat)abstract
- Plant traits-the morphological, anatomical, physiological, biochemical and phenological characteristics of plants-determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait-based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits-almost complete coverage for 'plant growth form'. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait-environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives.
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| 7. |
- Lis, D. C., et al.
(författare)
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Herschel/HIFI discovery of interstellar chloronium (H2Cl+)
- 2010
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Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 521:1
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Tidskriftsartikel (refereegranskat)abstract
- We report the first detection of chloronium, H_2Cl^+, in the interstellar medium, using the HIFI instrument aboard the Herschel Space Observatory. The 2_12-1_01 lines of ortho-H\_2^35Cl^+ and ortho-H\_2^37Cl^+ are detected in absorption towards NGC 6334I, and the 1_11-0_00 transition of para-H\_2^35Cl^+ is detected in absorption towards NGC 6334I and Sgr B2(S). The H_2Cl^+ column densities are compared to those of the chemically-related species HCl. The derived HCl/H_2Cl^+ column density ratios, ~1-10, are within the range predicted by models of diffuse and dense photon dominated regions (PDRs). However, the observed H_2Cl^+ column densities, in excess of 10^13 cm^-2, are significantly higher than the model predictions. Our observations demonstrate the outstanding spectroscopic capabilities of HIFI for detecting new interstellar molecules and providing key constraints for astrochemical models.
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| 8. |
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| 9. |
- Lefloch, B., et al.
(författare)
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The CHESS spectral survey of star forming regions : Peering into the protostellar shock L1157-B1. II. Shock dynamics
- 2010
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Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 518, s. L113-
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Tidskriftsartikel (refereegranskat)abstract
- Context. The outflow driven by the low-mass class 0 protostar L1157 is the prototype of the so-called chemically active outflows. The bright bowshock B1 in the southern outflow lobe is a privileged testbed of magneto-hydrodynamical (MHD) shock models, for which dynamical and chemical processes are strongly interdependent. Aims: We present the first results of the unbiased spectral survey of the L1157-B1 bowshock, obtained in the framework of the key program “Chemical HErschel Surveys of star forming regions” (CHESS). The main aim is to trace the warm and chemically enriched gas and to infer the excitation conditions in the shock region. Methods: The CO 5-4 and o-H2O 110-101 lines have been detected at high-spectral resolution in the unbiased spectral survey of the HIFI-band 1b spectral window (555-636 GHz), presented by Codella et al. in this volume. Complementary ground-based observations in the submm window help establish the origin of the emission detected in the main-beam of HIFI and the physical conditions in the shock. Results: Both lines exhibit broad wings, which extend to velocities much higher than reported up to now. We find that the molecular emission arises from two regions with distinct physical conditions : an extended, warm (100 K), dense (3 × 105 cm-3) component at low-velocity, which dominates the water line flux in Band 1; a secondary component in a small region of B1 (a few arcsec) associated with high-velocity, hot (>400 K) gas of moderate density ((1.0-3.0) × 104 cm-3), which appears to dominate the flux of the water line at 179μm observed with PACS. The water abundance is enhanced by two orders of magnitude between the low- and the high-velocity component, from 8 × 10-7 up to 8 × 10-5. The properties of the high-velocity component agree well with the predictions of steady-state C-shock models. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.
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| 10. |
- Hammen, V. C., et al.
(författare)
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Establishment of a cross-European field site network in the ALARM project for assessing large-scale changes in biodiversity
- 2010
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Ingår i: Environmental Monitoring & Assessment. - : Springer Science and Business Media LLC. - 1573-2959 .- 0167-6369. ; 164:1-4, s. 337-348
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Tidskriftsartikel (refereegranskat)abstract
- The field site network (FSN) plays a central role in conducting joint research within all Assessing Large-scale Risks for biodiversity with tested Methods (ALARM) modules and provides a mechanism for integrating research on different topics in ALARM on the same site for measuring multiple impacts on biodiversity. The network covers most European climates and biogeographic regions, from Mediterranean through central European and boreal to subarctic. The project links databases with the European-wide field site network FSN, including geographic information system (GIS)-based information to characterise the test location for ALARM researchers for joint on-site research. Maps are provided in a standardised way and merged with other site-specific information. The application of GIS for these field sites and the information management promotes the use of the FSN for research and to disseminate the results. We conclude that ALARM FSN sites together with other research sites in Europe jointly could be used as a future backbone for research proposals.
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| 11. |
- Vastel, C., et al.
(författare)
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Ortho-to-para ratio of interstellar heavy water
- 2010
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Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 521:1, s. Article Number: L31 -
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Tidskriftsartikel (refereegranskat)abstract
- Context. Despite the low elemental deuterium abundance in the Galaxy, enhanced molecular D/H ratios have been found in the environments of low-mass star-forming regions, and in particular the Class 0 protostar IRAS 16293-2422. Aims. The CHESS (Chemical HErschel Surveys of Star forming regions) key program aims to study the molecular complexity of the interstellar medium. The high sensitivity and spectral resolution of the Herschel/HIFI instrument provide a unique opportunity to observe the fundamental 1(1,1)-0(0,0) transition of the ortho-D2O molecule, which is inaccessible from the ground, and determine the ortho-to-para D2O ratio. Methods. We detected the fundamental transition of the ortho-D2O molecule at 607.35 GHz towards IRAS 16293-2422. The line is seen in absorption with a line opacity of 0.62 +/- 0.11 (1 sigma). From the previous ground-based observations of the fundamental 1(1,0)-1(0,1) transition of para-D2O seen in absorption at 316.80 GHz, we estimate a line opacity of 0.26 +/- 0.05 (1 sigma). Results. We show that the observed absorption is caused by the cold gas in the envelope of the protostar. Using these new observations, we estimate for the first time the ortho-to-para D2O ratio to be lower than 2.6 at a 3 sigma level of uncertainty, which should be compared with the thermal equilibrium value of 2:1.
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| 12. |
- Codella, C., et al.
(författare)
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The CHESS spectral survey of star forming regions : Peering into the protostellar shock L1157-B1. I. Shock chemical complexity
- 2010
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Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 518, s. L112-
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Tidskriftsartikel (refereegranskat)abstract
- We present the first results of the unbiased survey of the L1157-B1 bow shock, obtained with HIFI in the framework of the key program Chemical HErschel Survey of Star forming regions (CHESS). The L1157 outflow is driven by a low-mass Class 0 protostar and is considered the prototype of the so-called chemically active outflows. The bright blue-shifted bow shock B1 is the ideal laboratory for studying the link between the hot (~1000-2000 K) component traced by H2 IR-emission and the cold (~10-20 K) swept-up material. The main aim is to trace the warm gas chemically enriched by the passage of a shock and to infer the excitation conditions in L1157-B1. A total of 27 lines are identified in the 555-636 GHz region, down to an average 3σ level of 30 mK. The emission is dominated by CO(5-4) and H2O(110-101) transitions, as discussed by Lefloch et al. in this volume. Here we report on the identification of lines from NH3, H2CO, CH3OH, CS, HCN, and HCO+. The comparison between the profiles produced by molecules released from dust mantles (NH3, H2CO, CH3OH) and that of H2O is consistent with a scenario in which water is also formed in the gas-phase in high-temperature regions where sputtering or grain-grain collisions are not efficient. The high excitation range of the observed tracers allows us to infer, for the first time for these species, the existence of a warm (≥200 K) gas component coexisting in the B1 bow structure with the cold and hot gas detected from ground. Herschel is an ESA space observatory with science instruments provided by European-led principal Investigator consortia and with important participation from NASA.Table 1 is only available in electronic form at http://www.aanda.org
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| 13. |
- Klotz, K N, et al.
(författare)
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Comparative pharmacology of human adenosine receptor subtypes - characterization of stably transfected receptors in CHO cells
- 1998
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Ingår i: Naunyn-Schmiedeberg's Archives of Pharmacology. - 0028-1298. ; 357:1, s. 1-9
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Tidskriftsartikel (refereegranskat)abstract
- Four adenosine receptor subtypes of the family of G protein-coupled receptors, designated A1, A2A, A2B and A3 are currently known. In this study all human subtypes were stably transfected into Chinese hamster ovary (CHO) cells in order to be able to study their pharmacological profile in an identical cellular background utilizing radioligand binding studies (A1, A2A, A3) or adenylyl cyclase activity assays (A2B). The A1 subtype showed the typical pharmacological profile with 2-chloro-N6-cyclopentyladenosine (CCPA) as the agonist with the highest affinity and a marked stereoselectivity for the N6-phenylisopropyladenosine (PIA) diastereomers. In competition with antagonist radioligand biphasic curves were observed for agonists. In the presence of GTP all receptors were converted to a single low affinity state indicating functional coupling to endogenous G proteins. For A2A adenosine receptors CGS 21680 (2-[p-(2-carboxyethyl)phenylethylamino]-5'-N-ethylcarboxamidoadeno sine) and N-ethylcarboxamidoadenosine (NECA) were found to be the most potent agonists followed by R- and S-PIA with minor stereoselectivity. The relative potencies of agonists for the A2B adenosine receptor could only be tested by measurement of receptor-stimulated adenylyl cyclase activity. NECA was the most potent agonist with an EC50-value of 2.3 microM whereas all other compounds tested were active at concentrations in the high micromolar range. Inhibition of NECA-stimulated adenylyl cyclase identified xanthine amino congener (XAC; 8-[4-[[[[(2-aminoethyl)amino]-carbonyl]methyl]oxy]phenyl]-1,3-dipropylxa nthine) as the most potent antagonist at this receptor subtype. The A3 receptor was characterized utilizing the nonselective agonist [3H]NECA. The N6-benzyl substituted derivatives of adenosine-5'-N-methyluronamide (MECA) turned out to be the most potent agonists. The notion of xanthine-insensitivity of the A3 receptor should be dropped at least for the human receptor as xanthines with submicromolar affinity were found. Overall, the pharmacological characteristics of the human receptors are similar to other species with some species-specific characteristics. In this study we present for the first time the comparative pharmacology of all known human adenosine receptor subtypes. The CHO cells with stably transfected adenosine receptors provide an identical cellular background for such a pharmacological characterization. These cells are valuable systems for further characterization of specific receptor subtypes and for the development of new ligands.
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| 14. |
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| 15. |
- Aronson, M.F.J., et al.
(författare)
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A global analysis of the impacts of urbanization on bird and plant diversity reveals key anthropogenic drivers
- 2014
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Ingår i: Proceedings of the Royal Society of London. Biological Sciences. - : The Royal Society. - 0962-8452 .- 1471-2954. ; 281:1780, s. 20133330-
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Tidskriftsartikel (refereegranskat)abstract
- Urbanization contributes to the loss of the world's biodiversity and the homogenization of its biota. However, comparative studies of urban biodiversity leading to robust generalities of the status and drivers of biodiversity in cities at the global scale are lacking. Here, we compiled the largest global dataset to date of two diverse taxa in cities: birds (54 cities) and plants (110 cities). We found that the majority of urban bird and plant species are native in the world's cities. Few plants and birds are cosmopolitan, the most common being Columba livia and Poa annua. The density of bird and plant species (the number of species per km2) has declined substantially: only 8% of native bird and 25% of native plant species are currently present compared with estimates of non-urban density of species. The current density of species in cities and the loss in density of species was best explained by anthropogenic features (landcover, city age) rather than by non-anthropogenic factors (geography, climate, topography). As urbanization continues to expand, efforts directed towards the conservation of intact vegetation within urban landscapes could support higher concentrations of both bird and plant species. Despite declines in the density of species, cities still retain endemic native species, thus providing opportunities for regional and global biodiversity conservation, restoration and education.
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| 16. |
- Bruinsma, Sophie M, et al.
(författare)
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Expert consensus document : Semantics in active surveillance for men with localized prostate cancer - results of a modified Delphi consensus procedure
- 2017
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Ingår i: Nature Reviews Urology. - : Springer Science and Business Media LLC. - 1759-4820 .- 1759-4812. ; 14:5, s. 312-322
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Forskningsöversikt (refereegranskat)abstract
- Active surveillance (AS) is broadly described as a management option for men with low-risk prostate cancer, but semantic heterogeneity exists in both the literature and in guidelines. To address this issue, a panel of leading prostate cancer specialists in the field of AS participated in a consensus-forming project using a modified Delphi method to reach international consensus on definitions of terms related to this management option. An iterative three-round sequence of online questionnaires designed to address 61 individual items was completed by each panel member. Consensus was considered to be reached if ≥70% of the experts agreed on a definition. To facilitate a common understanding among all experts involved and resolve potential ambiguities, a face-to-face consensus meeting was held between Delphi survey rounds two and three. Convenience sampling was used to construct the panel of experts. In total, 12 experts from Australia, France, Finland, Italy, the Netherlands, Japan, the UK, Canada and the USA participated. By the end of the Delphi process, formal consensus was achieved for 100% (n = 61) of the terms and a glossary was then developed. Agreement between international experts has been reached on relevant terms and subsequent definitions regarding AS for patients with localized prostate cancer. This standard terminology could support multidisciplinary communication, reduce the extent of variations in clinical practice and optimize clinical decision making.
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| 17. |
- Ceccarelli, C., et al.
(författare)
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Herschel spectral surveys of star- forming regions Overview of the 555-636 GHz range
- 2010
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Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 521, s. L22-
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Tidskriftsartikel (refereegranskat)abstract
- High resolution line spectra of star-forming regions are mines of information: they provide unique clues to reconstruct the chemical, dynamical, and physical structure of the observed source. We present the first results from the Herschel key project " Chemical HErschel Surveys of Star forming regions", CHESS. We report and discuss observations towards five CHESS targets, one outflow shock spot and four protostars with luminosities bewteen 20 and 2 x 105 L similar to : L1157-B1, IRAS 16293-2422, OMC2-FIR4, AFGL 2591, and NGC 6334I. The observations were obtained with the heterodyne spectrometer HIFI on board Herschel, with a spectral resolution of 1 MHz. They cover the frequency range 555-636 GHz, a range largely unexplored before the launch of the Herschel satellite. A comparison of the five spectra highlights spectacular differences in the five sources, for example in the density of methanol lines, or the presence./absence of lines from S-bearing molecules or deuterated species. We discuss how these differences can be attributed to the different star-forming mass or evolutionary status.
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| 18. |
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| 19. |
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| 20. |
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| 21. |
- Lykou, F., et al.
(författare)
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Dissecting the AGB star L-2 Puppis : a torus in the making
- 2015
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Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 576
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Tidskriftsartikel (refereegranskat)abstract
- Aims. The circumstellar environment of L-2 Pup, an oxygen-rich semiregular variable, was observed to understand the evolution of mass loss and the shaping of ejecta in the late stages of stellar evolution. Methods. High-angular resolution observations from a single 8 m telescope were obtained using aperture masking in the near-infrared (1.64, 2.30 and 3.74 mu m) on the NACO/VLT, both in imaging and polarimetric modes. Results. The aperture-masking images of L-2 Pup at 2.30 mu m show a resolved structure that resembles a toroidal structure with a major axis of similar to 140 milliarcseconds (mas) and an east-west orientation. Two clumps can be seen on either side of the star, similar to 65 mas from the star, beyond the edge of the circumstellar envelope (estimated diameter is similar to 27 mas), while a faint, hook-like structure appear toward the northeast. The patterns are visible both in the imaging and polarimetric mode, although the latter was only used to measure the total intensity (Stokes I). The overall shape of the structure is similar at the 3.74 mu m pseudo-continuum (dust emission), where the clumps appear to be embedded within a dark, dusty lane. The faint, hook-like patterns are also seen at this wavelength, extending northeast and southwest with the central, dark lane being an apparent axis of symmetry. We interpret the structure as a circumstellar torus with inner radius of 4.2 au. With a rotation velocity of 10 kms(-1) as suggested by the SiO maser profile, we estimate a stellar mass of 0.7 M-circle dot.
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| 22. |
- Mackenbach, J. P., et al.
(författare)
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Variations in the relation between education and cause-specific mortality in 19 European populations : A test of the "fundamental causes" theory of social inequalities in health
- 2015
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Ingår i: Social Science and Medicine. - : Elsevier BV. - 0277-9536 .- 1873-5347. ; 127, s. 51-62
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Tidskriftsartikel (refereegranskat)abstract
- Link and Phelan have proposed to explain the persistence of health inequalities from the fact that socioeconomic status is a "fundamental cause" which embodies an array of resources that can be used to avoid disease risks no matter what mechanisms are relevant at any given time. To test this theory we compared the magnitude of inequalities in mortality between more and less preventable causes of death in 19 European populations, and assessed whether inequalities in mortality from preventable causes are larger in countries with larger resource inequalities.We collected and harmonized mortality data by educational level on 19 national and regional populations from 16 European countries in the first decade of the 21st century. We calculated age-adjusted Relative Risks of mortality among men and women aged 30-79 for 24 causes of death, which were classified into four groups: amenable to behavior change, amenable to medical intervention, amenable to injury prevention, and non-preventable.Although an overwhelming majority of Relative Risks indicate higher mortality risks among the lower educated, the strength of the education-mortality relation is highly variable between causes of death and populations. Inequalities in mortality are generally larger for causes amenable to behavior change, medical intervention and injury prevention than for non-preventable causes. The contrast between preventable and non-preventable causes is large for causes amenable to behavior change, but absent for causes amenable to injury prevention among women. The contrast between preventable and non-preventable causes is larger in Central & Eastern Europe, where resource inequalities are substantial, than in the Nordic countries and continental Europe, where resource inequalities are relatively small, but they are absent or small in Southern Europe, where resource inequalities are also large.In conclusion, our results provide some further support for the theory of "fundamental causes". However, the absence of larger inequalities for preventable causes in Southern Europe and for injury mortality among women indicate that further empirical and theoretical analysis is necessary to understand when and why the additional resources that a higher socioeconomic status provides, do and do not protect against prevailing health risks.
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| 23. |
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| 24. |
- Van Hemelrijck, Mieke, et al.
(författare)
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Reasons for Discontinuing Active Surveillance : Assessment of 21 Centres in 12 Countries in the Movember GAP3 Consortium
- 2019
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Ingår i: European Urology. - : Elsevier BV. - 0302-2838. ; 75:3, s. 523-531
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Tidskriftsartikel (refereegranskat)abstract
- Background: Careful assessment of the reasons for discontinuation of active surveillance (AS) is required for men with prostate cancer (PCa). Objective: Using Movember's Global Action Plan Prostate Cancer Active Surveillance initiative (GAP3) database, we report on reasons for AS discontinuation. Design, setting, and participants: We compared data from 10 296 men on AS from 21 centres across 12 countries. Outcome measurements and statistical analysis: Cumulative incidence methods were used to estimate the cumulative incidence rates of AS discontinuation. Results and limitations: During 5-yr follow-up, 27.5% (95% confidence interval [CI]: 26.4–28.6%) men showed signs of disease progression, 12.8% (95% CI: 12.0–13.6%) converted to active treatment without evidence of progression, 1.7% (95% CI: 1.5–2.0%) continued to watchful waiting, and 1.7% (95% CI: 1.4–2.1%) died from other causes. Of the 7049 men who remained on AS, 2339 had follow-up for >5 yr, 4561 had follow-up for <5 yr, and 149 were lost to follow-up. Cumulative incidence of progression was 27.5% (95% CI: 26.4–28.6%) at 5 yr and 38.2% (95% CI: 36.7–39.9%) at 10 yr. A limitation is that not all centres were included due to limited information on the reason for discontinuation and limited follow-up. Conclusions: Our descriptive analyses of current AS practices worldwide showed that 43.6% of men drop out of AS during 5-yr follow-up, mainly due to signs of disease progression. Improvements in selection tools for AS are thus needed to correctly allocate men with PCa to AS, which will also reduce discontinuation due to conversion to active treatment without evidence of disease progression. Patient summary: Our assessment of a worldwide database of men with prostate cancer (PCa) on active surveillance (AS) shows that 43.6% drop out of AS within 5 yr, mainly due to signs of disease progression. Better tools are needed to select and monitor men with PCa as part of AS.
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| 25. |
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| 26. |
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| 27. |
- Andrade, Luis E. C., et al.
(författare)
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International consensus on antinuclear antibody patterns : definition of the AC-29 pattern associated with antibodies to DNA topoisomerase I
- 2018
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Ingår i: Clinical Chemistry and Laboratory Medicine. - : WALTER DE GRUYTER GMBH. - 1434-6621 .- 1437-4331. ; 56:10, s. 1783-1788
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Tidskriftsartikel (refereegranskat)abstract
- The indirect immunofluorescence assay (IFA) on HEp-2 cells is the reference method for autoantibody screening. The HEp-2 IFA pattern provides useful information on the possible autoantibodies in the sample. The International Consensus on Antinuclear Antibody Patterns (ICAP) initiative seeks to define and harmonize the nomenclature of HEp-2 IFA patterns. The most relevant and usual patterns have been assigned an alphanumeric code from anti-cell (AC)-1 to AC-28 and were organized into a classification algorithm (www.ANApatterns.org). The systemic sclerosis-associated autoantibodies to DNA topoisomerase I (Topo I) produce a peculiar composite 5-element HEp-2 IFA pattern (Topo I-like pattern) comprising the staining of the nucleus, metaphase chromatin plate, nucleolar organizing region, cytoplasm and nucleolus. In a recent assessment of the European Consensus Finding Study Group on autoantibodies, a well-defined anti-Topo I sample was blindly analyzed and classified according to ICAP AC patterns by 43 participant laboratories across Europe. There were wide variations among these laboratories in reporting nuclear, nucleolar and cytoplasmic patterns, indicating the inadequacy of the existing AC patterns to report the Topo I-like pattern. Several ICAP member laboratories independently demonstrated the overall consistency of the HEp-2 IFA Topo I-like pattern using HEp-2 slides from different manufacturers. The ICAP committee reviewed 24 candidate images and selected the four most representative images to be available on the ICAP website. The proper recognition of the AC-29 pattern should trigger suspicion of the presence of anti-Topo I antibodies, which may engender appropriate analyte-specific reflex tests to confirm the autoantibody specificity.
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| 28. |
- Bjornstad, T., et al.
(författare)
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Study of the Giant Gamow-Teller Resonance in Nuclear Beta-Decay - the Case of Ar-32
- 1985
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Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474. ; 443:2, s. 283-301
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Tidskriftsartikel (refereegranskat)abstract
- Delayed proton and gamma emissions following the β-decay of 32Ar have been studied. The half-life of 32Ar is 98 ± 2 ms, and the T = 2 analogue state in 32Cl lies at the excitation energy 5036 ± 12 keV. From the intensity of the feeding to this state the proton intensities can be converted to an absolute scale leading to a total proton branching ratio of (43 ± 3)%. From proton-gamma coincidence measurements it emerges that (1.9 ± 0.2)% of the protons lead to the first-excited state in 31S. A level scheme up to 8.75 MeV excitation in 32Cl has been constructed and the Gamow-Teller strength function has been deduced. The result is a renormalization of the axial-vector strength to (49 ± 5)% of the free-nucleon value.
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| 29. |
- Borge, M. J. G., et al.
(författare)
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Study of the Giant Gamow-Teller Resonance in Nuclear Beta-Decay - the Case of Ar-33
- 1987
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Ingår i: Physica Scripta. - : IOP Publishing. - 1402-4896 .- 0031-8949. ; 36:2, s. 218-223
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Tidskriftsartikel (refereegranskat)abstract
- Delayed proton and gamma emissions following the beta decay of 33Ar have been studied. From the calculated intensity of the feeding to the T = 3/2 analogue state in 33C1, the proton intensities have been put on an absolute scale leading to a proton branching ratio of 38.7 ± 1.0%. A proton branch to the first excited state in 32S at 2230.2 keV (1π = 2+) with an intensity of 0.77 ± 0.10% was obtained from gamma singles and proton-gamma coincidence data. The complete spectroscopic information on 33Ar allows the Gamow-Teller (GT) strength function from the gound state and up to 9.25 MeV excitation energy in 33C1 to be deduced. The total strength observed in this interval is 2.90 in absolute units.
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| 30. |
- Dall'Era, Marc A., et al.
(författare)
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Active surveillance for early-stage prostate cancer : review of the current literature
- 2008
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Ingår i: Cancer. - : Wiley. - 0008-543X .- 1097-0142. ; 112:8, s. 1650-9
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Tidskriftsartikel (refereegranskat)abstract
- The natural history of prostate cancer is remarkably heterogeneous and, at this time, not completely understood. The widespread adoption and application of prostate-specific antigen (PSA) screening has led to a dramatic shift toward the diagnosis of low-volume, nonpalpable, early-stage tumors. Autopsy and early observational studies have shown that approximately 1 in 3 men aged >50 years has histologic evidence of prostate cancer, with a significant portion of tumors being small and possibly clinically insignificant. Utilizing the power of improved contemporary risk stratification schema to better identify patients with a low risk of cancer progression, several centers are gaining considerable experience with active surveillance and delayed, selective, and curative therapy. A literature review was performed to evaluate the rationale behind active surveillance for prostate cancer and to describe the early experiences from surveillance protocols. It appears that a limited number of men on active surveillance have required treatment, with the majority of such men having good outcomes after delayed selective intervention for progressive disease. The best candidates for active surveillance are being defined, as are predictors of active treatment. The psychosocial ramifications of surveillance for prostate cancer can be profound and future needs and unmet goals will be discussed.
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| 31. |
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| 32. |
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| 33. |
- Joeris, Thorsten, et al.
(författare)
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Intestinal cDC1 drive cross-tolerance to epithelial-derived antigen via induction of FoxP3+CD8+ Tregs
- 2021
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Ingår i: Science Immunology. - : American Association for the Advancement of Science (AAAS). - 2470-9468. ; 6:60
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Tidskriftsartikel (refereegranskat)abstract
- Although CD8+ T cell tolerance to tissue-specific antigen (TSA) is essential for host homeostasis, the mechanisms underlying peripheral cross-tolerance and whether they may differ between tissue sites remain to be fully elucidated. Here, we demonstrate that peripheral cross-tolerance to intestinal epithelial cell (IEC)–derived antigen involves the generation and suppressive function of FoxP3+CD8+ T cells. FoxP3+CD8+ Treg generation was dependent on intestinal cDC1, whose absence led to a break of tolerance and epithelial destruction. Mechanistically, intestinal cDC1-derived PD-L1, TGFβ, and retinoic acid contributed to the generation of gut-tropic CCR9+CD103+FoxP3+CD8+ Tregs. Last, CD103-deficient CD8+ T cells lacked tolerogenic activity in vivo, indicating a role for CD103 in FoxP3+CD8+ Treg function. Our results describe a role for FoxP3+CD8+ Tregs in cross-tolerance in the intestine for which development requires intestinal cDC1.
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| 34. |
- Kasivisvanathan, Veeru, et al.
(författare)
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MRI-targeted or standard biopsy for prostate-cancer diagnosis
- 2018
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Ingår i: New England Journal of Medicine. - 0028-4793. ; 378:19, s. 1767-1777
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Multiparametric magnetic resonance imaging (MRI), with or without targeted biopsy, is an alternative to standard transrectal ultrasonography-guided biopsy for prostate-cancer detection in men with a raised prostate-specific antigen level who have not undergone biopsy. However, comparative evidence is limited. METHODS: In a multicenter, randomized, noninferiority trial, we assigned men with a clinical suspicion of prostate cancer who had not undergone biopsy previously to undergo MRI, with or without targeted biopsy, or standard transrectal ultrasonography-guided biopsy. Men in the MRI-targeted biopsy group underwent a targeted biopsy (without standard biopsy cores) if the MRI was suggestive of prostate cancer; men whose MRI results were not suggestive of prostate cancer were not offered biopsy. Standard biopsy was a 10-to-12-core, transrectal ultrasonography-guided biopsy. The primary outcome was the proportion of men who received a diagnosis of clinically significant cancer. Secondary outcomes included the proportion of men who received a diagnosis of clinically insignificant cancer. RESULTS: A total of 500 men underwent randomization. In the MRI-targeted biopsy group, 71 of 252 men (28%) had MRI results that were not suggestive of prostate cancer, so they did not undergo biopsy. Clinically significant cancer was detected in 95 men (38%) in the MRI-targeted biopsy group, as compared with 64 of 248 (26%) in the standard-biopsy group (adjusted difference, 12 percentage points; 95% confidence interval [CI], 4 to 20; P = 0.005). MRI, with or without targeted biopsy, was noninferior to standard biopsy, and the 95% confidence interval indicated the superiority of this strategy over standard biopsy. Fewer men in the MRI-targeted biopsy group than in the standard-biopsy group received a diagnosis of clinically insignificant cancer (adjusted difference, -13 percentage points; 95% CI, -19 to -7; P<0.001). CONCLUSIONS: The use of risk assessment with MRI before biopsy and MRI-targeted biopsy was superior to standard transrectal ultrasonography-guided biopsy in men at clinical risk for prostate cancer who had not undergone biopsy previously. (Funded by the National Institute for Health Research and the European Association of Urology Research Foundation; PRECISION ClinicalTrials.gov number, NCT02380027.)
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| 35. |
- Klotz, D., et al.
(författare)
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Catching the fish - Constraining stellar parameters for TX Piscium using spectro-interferometric observations
- 2013
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Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 550, s. A86-
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Tidskriftsartikel (refereegranskat)abstract
- Context. Stellar parameter determination is a challenging task when dealing with galactic giant stars. The combination of different investigation techniques has proven to be a promising approach. Aims. We analyse archive spectra obtained with the Short Wavelength Spectrometer (SWS) onboard ISO, and new interferometric observations from the Very Large Telescope MID-infrared Interferometric instrument (VLTI/MIDI) of a very well studied carbon-rich giant: TXPsc. The aim of this work is to determine stellar parameters using spectroscopy and interferometry. Methods. The observations are used to constrain the model atmosphere, and eventually the stellar evolutionary model in the region where the tracks map the beginning of the carbon star sequence. Two different approaches are used to determine stellar parameters: (i) the "classic" interferometric approach where the effective temperature is fixed by using the angular diameter in the N-band (from interferometry) and the apparent bolometric magnitude; (ii) parameters are obtained by fitting a grid of state-of-the-art hydrostatic models to spectroscopic and interferometric observations. Results. We find good agreement between the parameters of the two methods. The effective temperature and luminosity clearly place TXPsc in the carbon-rich AGB star domain in the H-R-diagram. Current evolutionary tracks suggest that TXPsc became a C-star just recently, which means that the star is still in a "quiet" phase compared to the subsequent strong-wind regime. This agrees with the C/O ratio being only slightly greater than one.
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| 36. |
- Klotz, D., et al.
(författare)
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Geometrical model fitting for interferometric data : GEM-FIND
- 2012
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Ingår i: Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series. - : SPIE.
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Konferensbidrag (refereegranskat)abstract
- We developed the tool GEM-FIND that allows to constrain the morphology and brightness distribution of ob- jects. The software fits geometrical models to spectrally dispersed interferometric visibility measurements in the N-band using the Levenberg-Marquardt minimization method. Each geometrical model describes the bright- ness distribution of the object in the Fourier space using a set of wavelength-independent and/or wavelength- dependent parameters. In this contribution we numerically analyze the stability of our nonlinear fitting approach by applying it to sets of synthetic visibilities with statistically applied errors, answering the following questions: How stable is the parameter determination with respect to (i) the number of uv-points, (ii) the distribution of points in the uv-plane, (iii) the noise level of the observations?
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| 37. |
- Klotz, D., et al.
(författare)
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The geometry of the close environment of SV Piscium as probed by VLTI/MIDI
- 2012
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Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 541
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Tidskriftsartikel (refereegranskat)abstract
- Context. SVPsc is an asymptotic giant branch (AGB) star surrounded by an oxygen-rich dust envelope. The mm-CO line profile of the object's outflow shows a clear double-component structure. Because of the high angular resolution, mid-IR interferometry may give strong constraints on the origin of this composite profile. Aims. The aim of this work is to investigate the morphology of the environment around SVPsc using high-angular resolution interferometry observations in the mid-IR with the Very Large Telescope MID-infrared Interferometric instrument (VLTI/MIDI). Methods. Interferometric data in the N-band taken at different baseline lengths (ranging from 32-64 m) and position angles (73-142 degrees) allow a study of the morphology of the circumstellar environment close to the star. The data are interpreted on the basis of 2-dimensional, chromatic geometrical models using the fitting software tool GEM-FIND developed for this purpose. Results. The results favor two scenarios: (i) the presence of a highly inclined, optically thin, dusty disk surrounding the central star; (ii) the presence of an unresolved binary companion at a separation of 13.7(-4.8)(+4.2) AU and a position angle of 121.8 degrees(-24.5)degrees(+15.4)degrees. NE. The derived orbital period of the binary is 38.1(-22.6)(+20.4) yr. This detection is in good agreement with hydrodynamic simulations showing that a close companion could be responsible for the entrainment of the gas and dust into a circumbinary structure.
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| 38. |
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| 39. |
- Lange, Jane M., et al.
(författare)
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Prostate cancer mortality and metastasis under different biopsy frequencies in North American active surveillance cohorts
- 2020
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Ingår i: Cancer. - : WILEY. - 0008-543X .- 1097-0142. ; 126:3, s. 583-592
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Tidskriftsartikel (refereegranskat)abstract
- Background Active surveillance (AS) is an accepted means of managing low-risk prostate cancer. Because of the rarity of downstream events, data from existing AS cohorts cannot yet address how differences in surveillance intensity affect metastasis and mortality. This study projected the comparative benefits of different AS schedules in men diagnosed with prostate cancer who had Gleason score (GS) <= 6 disease and risk profiles similar to those in North American AS cohorts. Methods Times of GS upgrading were simulated based on AS data from the University of Toronto, Johns Hopkins University, the University of California at San Francisco, and the Canary Pass Active Surveillance Cohort. Times to metastasis and prostate cancer death, informed by models from the Scandinavian Prostate Cancer Group 4 trial, were projected under biopsy surveillance schedules ranging from watchful waiting to annual biopsies. Outcomes included the risk of metastasis, the risk of death, remaining life-years (LYs), and quality-adjusted LYs. Results Compared with watchful waiting, AS biopsies reduced the risk of prostate cancer metastasis and prostate cancer death at 20 years by 1.4% to 3.3% and 1.0% to 2.4%, respectively; and 5-year biopsies reduced the risk of metastasis and prostate cancer death by 1.0% to 2.4% and 0.6% to 1.6%, respectively. There was little difference between annual and 5-year biopsy schedules in terms of LYs (range of differences, 0.04-0.16 LYs) and quality-adjusted LYs (range of differences, -0.02 to 0.09 quality-adjusted LYs). Conclusions Among men diagnosed with GS <= 6 prostate cancer, obtaining a biopsy every 3 or 4 years appears to be an acceptable alternative to more frequent biopsies. Reducing surveillance intensity for those who have a low risk of progression reduces the number of biopsies while preserving the benefit of more frequent schedules.
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| 40. |
- Marazioti, Antonia, et al.
(författare)
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KRAS signaling in malignant pleural mesothelioma
- 2022
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Ingår i: EMBO Molecular Medicine. - : EMBO. - 1757-4684 .- 1757-4676. ; 14:2
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Tidskriftsartikel (refereegranskat)abstract
- Malignant pleural mesothelioma (MPM) arises from mesothelial cells lining the pleural cavity of asbestos-exposed individuals and rapidly leads to death. MPM harbors loss-of-function mutations in BAP1, NF2, CDKN2A, and TP53, but isolated deletion of these genes alone in mice does not cause MPM and mouse models of the disease are sparse. Here, we show that a proportion of human MPM harbor point mutations, copy number alterations, and overexpression of KRAS with or without TP53 changes. These are likely pathogenic, since ectopic expression of mutant KRASG12D in the pleural mesothelium of conditional mice causes epithelioid MPM and cooperates with TP53 deletion to drive a more aggressive disease form with biphasic features and pleural effusions. Murine MPM cell lines derived from these tumors carry the initiating KRASG12D lesions, secondary Bap1 alterations, and human MPM-like gene expression profiles. Moreover, they are transplantable and actionable by KRAS inhibition. Our results indicate that KRAS alterations alone or in accomplice with TP53 alterations likely play an important and underestimated role in a proportion of patients with MPM, which warrants further exploration.
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| 41. |
- Miller, Kurt, et al.
(författare)
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The continuing role of PSA in the detection and management of prostate cancer
- 2007
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Ingår i: European Urology. Supplement. - : Elsevier BV. - 1569-9056. ; 6:3, s. 327-333
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Tidskriftsartikel (refereegranskat)abstract
- Despite being used extensively for the diagnosis and management of prostate cancer, prostate-specific antigen (PSA) testing remains controversial. Doubts have been raised over the continued use of PSA in the detection of clinically significant prostate cancer because many men now present with early-stage, small-volume tumours. This article examines the limitations of using a single PSA value in diagnosis and discusses alternative approaches to PSA testing, in particular PSA velocity and PSA doubling time, which are now emerging as valuable pretreatment disease predictors. A clinical scenario is also presented to illustrate the use of PSA kinetics in identifying candidates for biopsy. (c) 2006 European Association of Urology. Published by Elsevier B.V. All rights reserved.
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| 42. |
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| 43. |
- Nelson, Adam J., et al.
(författare)
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Cardiovascular Effects of GnRH Antagonists Compared With Agonists in Prostate Cancer : A Systematic Review
- 2023
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Ingår i: JACC: CardioOncology. - 2666-0873. ; 5:5, s. 613-624
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Forskningsöversikt (refereegranskat)abstract
- Background: Androgen deprivation therapy is the cornerstone of treatment for patients with advanced prostate cancer. Meta-analysis of small, oncology-focused trials suggest gonadotropin-releasing hormone (GnRH) antagonists may be associated with fewer adverse cardiovascular outcomes compared with GnRH agonists. Objectives: This study sought to determine whether GnRH antagonists were associated with fewer major adverse cardiovascular events compared with GnRH agonists. Methods: Electronic databases were searched for all prospective, randomized trials comparing GnRH antagonists with agonists. The primary outcome was a major adverse cardiovascular event as defined by the following standardized Medical Dictionary for Regulatory Activities terms: “myocardial infarction,” “central nervous system hemorrhages and cerebrovascular conditions,” and all-cause mortality. Bayesian meta-analysis models with random effects were fitted. Results: A total of 11 eligible studies of a maximum duration of 3 to 36 months (median = 12 months) enrolling 4,248 participants were included. Only 1 trial used a blinded, adjudicated event process, whereas potential bias persisted in all trials given their open-label design. A total of 152 patients with primary outcome events were observed, 76 of 2,655 (2.9%) in GnRH antagonist-treated participants and 76 of 1,593 (4.8%) in agonist-treated individuals. Compared with GnRH agonists, the pooled OR of GnRH antagonists for the primary endpoint was 0.57 (95% credible interval: 0.37-0.86) and 0.58 (95% credible interval: 0.32-1.08) for all-cause death. Conclusions: Despite the addition of the largest, dedicated cardiovascular outcome trial, the volume and quality of available data to definitively answer this question remain suboptimal. Notwithstanding these limitations, the available data suggest that GnRH antagonists are associated with fewer cardiovascular events, and possibly mortality, compared with GnRH agonists.
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| 44. |
- Overbey, Eliah G., et al.
(författare)
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Challenges and considerations for single-cell and spatially resolved transcriptomics sample collection during spaceflight
- 2022
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Ingår i: CELL REPORTS METHODS. - : Elsevier BV. - 2667-2375. ; 2:11
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Forskningsöversikt (refereegranskat)abstract
- Single-cell RNA sequencing (scRNA-seq) and spatially resolved transcriptomics (SRT) have experienced rapid development in recent years. The findings of spaceflight-based scRNA-seq and SRT investigations are likely to improve our understanding of life in space and our comprehension of gene expression in various cell systems and tissue dynamics. However, compared to their Earth-based counterparts, gene expression experiments conducted in spaceflight have not experienced the same pace of development. Out of the hundreds of spaceflight gene expression datasets available, only a few used scRNA-seq and SRT. In this perspective piece, we explore the growing importance of scRNA-seq and SRT in space biology and discuss the challenges and considerations relevant to robust experimental design to enable growth of these methods in the field.
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| 45. |
- Paladini, C., et al.
(författare)
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Detection of an asymmetry in the envelope of the carbon Mira R Fornacis using VLTI/MIDI
- 2012
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Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 544, s. L5-
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Tidskriftsartikel (refereegranskat)abstract
- Aims. We present a study of the envelope morphology of the carbon Mira R For with VLTI/MIDI. This object is one of the few asymptotic giant branch (AGB) stars that underwent a dust-obscuration event. The cause of such events is still a matter of discussion. Several symmetric and asymmetric scenarios have been suggested in the literature.Methods. Mid-infrared interferometric observations were obtained separated by two years. The observations probe different depths of the atmosphere and cover different pulsation phases. The visibilities and the differential phases were interpreted using GEM-FIND, a tool for fitting spectrally dispersed interferometric observations with the help of wavelength-dependent geometric models.Results. We report the detection of an asymmetric structure revealed through the MIDI differential phase. This asymmetry is observed at the same baseline and position angle two years later. The observations are best simulated with a model that includes a uniform-disc plus a Gaussian envelope plus a point-source. The geometric model can reproduce both the visibilities and the differential phase signatures.Conclusions. Our MIDI data favour explanations of the R For obscuration event that are based on an asymmetric geometry. We clearly detect a photocentre shift between the star and the strongly resolved dust component. This might be caused by a dust clump or a substellar companion. However, the available observations do not allow us to distinguish between the two options. The finding has strong implications for future studies of the geometry of the envelope of AGB stars: if this is a binary, are all AGB stars that show an obscuration event binaries as well? Or are we looking at asymmetric mass-loss processes (i.e. dusty clumps) in the inner part of a carbon-rich Mira?
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| 46. |
- Paladini, C., et al.
(författare)
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The VLTI/MIDI view on the inner mass loss of evolved stars from the Herschel MESS sample
- 2017
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Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 600
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Tidskriftsartikel (refereegranskat)abstract
- Context. The mass-loss process from evolved stars is a key ingredient for our understanding of many fields of astrophysics, including stellar evolution and the chemical enrichment of the interstellar medium (ISM) via stellar yields. Nevertheless, many questions are still unsolved, one of which is the geometry of the mass-loss process. Aims. Taking advantage of the results from the Herschel Mass loss of Evolved StarS (MESS) programme, we initiated a coordinated effort to characterise the geometry of mass loss from evolved red giants at various spatial scales. Methods. For this purpose we used the MID-infrared interferometric Instrument (MIDI) to resolve the inner envelope of 14 asymptotic giant branch stars (AGBs) in the MESS sample. In this contribution we present an overview of the interferometric data collected within the frame of our Large Programme, and we also add archive data for completeness. We studied the geometry of the inner atmosphere by comparing the observations with predictions from different geometric models. Results. Asymmetries are detected for the following five stars: R Leo, RT Vir, ?1Gruis, omi Ori, and R Crt. All the objects are O-rich or S-type, suggesting that asymmetries in the N band are more common among stars with such chemistry. We speculate that this fact is related to the characteristics of the dust grains. Except for one star, no interferometric variability is detected, i.e. the changes in size of the shells of non-mira stars correspond to changes of the visibility of less than 10%. The observed spectral variability confirms previous findings from the literature. The detection of dust in our sample follows the location of the AGBs in the IRAS colour-colour diagram: More dust is detected around oxygen-rich stars in region II and in the carbon stars in region VII. The SiC dust feature does not appear in the visibility spectrum of the U Ant and S Sct, which are two carbon stars with detached shells. This finding has implications for the theory of SiC dust formation.
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| 47. |
- Paladini, C., et al.
(författare)
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To be or not to be asymmetric? VLTI and the mass loss geometry of red giants
- 2012
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Ingår i: Proceedings of SPIE - The International Society for Optical Engineering. - : SPIE. - 0277-786X .- 1996-756X. - 9780819491466 ; 8445, s. Art. no. 84451R-
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Konferensbidrag (refereegranskat)abstract
- The mass-loss process is a key ingredient for our understanding in many fields of astrophysics, including stellar evolution and the enrichment of the interstellar medium (ISM) via stellar yields. We combined the capability of the VLTI/MIDI and VLT/VISIR instruments with very recent Herschel/PACS observations to characterize the geometry of mass loss from evolved red giants on the Asymptotic Giant Branch (AGB) at various scales. This paper describes the sample of objects, the observing strategy, the tool for the interpretation, and preliminary MIDI results for two targets: U Ant and θ Aps.
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| 48. |
- Paladini, C., et al.
(författare)
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VLTI/MIDI Large Program: AGB Stars at Different Spatial Scales
- 2015
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Ingår i: Conference on Why Galaxies Care About AGB Stars III: A Closer Look in Space and Time, Vienna, Austria, JUL 28-AUG 01, 2014. - 9781583818794 ; 497, s. 97-102
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Konferensbidrag (refereegranskat)abstract
- We have observed a sample of Asymptotic Giant Branch (AGB) stars from the Herschel Mass-loss of Evolved StarS (MESS) program with the VLTI MID infrared Interferometric instrument (MIDI). The program aims at providing insight to the atmospheres of those stars, to be able to understand the role of the mass-loss process at different spatial scales. We obtained visibilities and spectra of fourteen objects with different chemistries and variability classes. These observations, together with data we retrieved from the archive, allow us to characterize not only the geometry of the dust forming region, but in some cases also the time variability in the N band. As previously reported in the literature, we confirm the detection of spectroscopic but not interferometric variability. This result has implications on the size of the structures involved in the dust-formation process. We also report two cases of asymmetric structures; the nature of these structures will be clearly identified only with the second generation VLTI instrument MATISSE.
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| 49. |
- Ristorcelli, I., et al.
(författare)
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Odin observation of water in the IRAS 16293-2422 low-mass star forming region
- 2005
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Ingår i: Astrochemistry: Recent Successes and Current Challenges. ; , s. 227P-
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- We present the Odin satellite submillimeter measurement of the ground state transition of ortho-water at 557 GHz around the low-mass protostar IRAS16293-2422. The three following regions have been probed: the on-source position, and the two regions of interaction between the molecular outflows and the dense ambient cloud, i .e. on the SiO peak E1, and near the deuterated peak (cf Lis et al.(2002)). The three spectra reveal broad emission, with a narrow and deep absorption feature at the velocity of the quiescent gas. The water line profiles and intensities have been compared and combined with the CO(3- 2) and HCO+ lines from Lis et al.(2002) after convolution over the Odin beam. The contribution from the central envelope on the water line emission has been estimated with the infall model of Shoier et al. 2002. We show that the water emission is dominated by the outflows, particularly in the red wing of the lines. Using a c-shock modelling (Cabrit et al. 2005), we derive an abundance of X(H2O) 1 - 3 × 10-5 of H2, and shock velocities of 12 - 15 km/s. We also show that the absorption feature is due to the cold outer halo and corresponds to a lower limit of a few 10-9 on the H2O abundance.
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| 50. |
- Williamson, M., et al.
(författare)
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The distribution of range sizes of native and alien plants in four European countries and the effects of residence time
- 2008
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Ingår i: Diversity & distributions. - : Wiley. - 1366-9516 .- 1472-4642. ; 15, s. 158-166
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Tidskriftsartikel (refereegranskat)abstract
- AimDo the statistical distributions of range sizes of native and alien species differ? If so, is this because of residence time effects? And can such effects indicate an average time to a maximum?LocationIreland, Britain, Germany and the Czech Republic.MethodsThe data are presence or absence of higher plants in mapping units of 100 km² (Ireland and Britain) or c. 130 km² (Germany and the Czech Republic) in areas varying from 79 to 357 thousand km². Logit transforms of range sizes so defined were tested for normality, and examined by ANOVA, and by loess, ordinary least square (OLS) and reduced major axis regressions.ResultsCurrent range sizes, in logits, are near normally distributed. Those of native plants are larger than those of naturalized neophytes (plants introduced since 1500 ad) and much larger than those of casual neophytes. Archaeophytes (introduced earlier) have range sizes slightly larger than natives, except in Ireland. Residence time, the time since an invasivespecies arrived in the wild at a certain place, affects range sizes. The relationships of the range of naturalized neophytes to residence time are effectively straight in all four places, showing no significant curvature or asymptote back to 1500, though there are few records between 1500 and 1800. The relationships have an r² of only about 10%. Both OLS regressions and reduced major axes can be used to estimate the time it takes for the range of a naturalized neophyte to reach a maximum.Main conclusionsEstablished neophytes have smaller range size distributions than natives probably because many have not yet reached their maximum. We estimate it takes at least 150 years, possibly twice that, on average, for the maximum to be reached in areas of the order of 105 km². Policy needs to allow for the variation in rates of spread and particularly the long time needed to fill ranges. Most naturalized neophytes are still expanding their ranges in Europe.
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