| 11. |
- Romero-Cañizales, C., et al.
(author)
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The nature of supernovae 2010O and 2010P in Arp 299 - II. Radio emission
- 2014
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In: Monthly Notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 440:2, s. 1067-1079
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Journal article (peer-reviewed)abstract
- We report radio observations of two stripped-envelope supernovae (SNe), 2010O and 2010P, which exploded within a few days of each other in the luminous infrared galaxy Arp 299. Whilst SN 2010O remains undetected at radio frequencies, SN 2010P was detected (with an astrometric accuracy better than 1 milli arcsec in position) in its optically thin phase in epochs ranging from similar to 1 to similar to 3 yr after its explosion date, indicating a very slow radio evolution and a strong interaction of the SN ejecta with the circumstellar medium. Our late-time radio observations towards SN 2010P probe the dense circumstellar envelope of this SN, and imply M [M-circle dot yr(-1)]/upsilon(wind) [10 km s(-1)] = (3.0 - 5.1) x 10(-5), with a 5 GHz peak luminosity of similar to 1.2 x 10(27) erg s(- 1) Hz(- 1) on day similar to 464 after explosion. This is consistent with a Type IIb classification for SN 2010P, making it the most distant and most slowly evolving Type IIb radio SN detected to date.
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| 12. |
- Barron, Jennie, et al.
(author)
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Drivers and Challenges for Food Security
- 2013
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In: Managing water and agroecosystems for food security. - Wallingford : CABI Publishing. - 9781780640884 ; , s. 7-28
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Book chapter (peer-reviewed)abstract
- At the global scale, humanity is increasingly facing rapid changes, and sometimes shocks, that are affecting the security of our food systems and the agroecosystems that are the ultimate sources of food. To plan and prepare for resilient food production and food security in a sustainable and efficient way, we are challenged to better understand the conditions and likely responses of these diverse agroecosystems under various drivers of change and scenarios of future trends. Among the many direct drivers and indirect pressures that exist or are emerging, the discussion in this chapter focuses on the main themes of drivers of demographic changes, globalization of economic and governance systems (including markets), and climate change. The current state of health of water and land resources, and of ecosystems and their services, are considered alongside these drivers, as these are critical determinants of the pathways with sufficient potential to move food-producing systems towards more sustainable production. Hence, addressing the opportunities, synergies and constraints of multiple drivers will be critical for policy advice to build resilient food systems in the future.
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| 13. |
- Bateman, Alex, et al.
(author)
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RNAcentral: A vision for an international database of RNA sequences.
- 2011
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In: RNA (New York, N.Y.). - : Cold Spring Harbor Laboratory. - 1469-9001 .- 1355-8382. ; 17:11, s. 1941-6
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Journal article (peer-reviewed)abstract
- During the last decade there has been a great increase in the number of noncoding RNA genes identified, including new classes such as microRNAs and piRNAs. There is also a large growth in the amount of experimental characterization of these RNA components. Despite this growth in information, it is still difficult for researchers to access RNA data, because key data resources for noncoding RNAs have not yet been created. The most pressing omission is the lack of a comprehensive RNA sequence database, much like UniProt, which provides a comprehensive set of protein knowledge. In this article we propose the creation of a new open public resource that we term RNAcentral, which will contain a comprehensive collection of RNA sequences and fill an important gap in the provision of biomedical databases. We envision RNA researchers from all over the world joining a federated RNAcentral network, contributing specialized knowledge and databases. RNAcentral would centralize key data that are currently held across a variety of databases, allowing researchers instant access to a single, unified resource. This resource would facilitate the next generation of RNA research and help drive further discoveries, including those that improve food production and human and animal health. We encourage additional RNA database resources and research groups to join this effort. We aim to obtain international network funding to further this endeavor.
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| 14. |
- Burillo, S. G., et al.
(author)
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Molecular line emission in NGC 1068 imaged with ALMA : I. An AGN-driven outflow in the dense molecular gas
- 2014
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In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 567, s. 125-
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Journal article (peer-reviewed)abstract
- Aims. We investigate the fueling and the feedback of star formation and nuclear activity in NGC 1068, a nearby (D = 14 Mpc) Seyfert 2 barred galaxy, by analyzing the distribution and kinematics of the molecular gas in the disk. We aim to understand if and how gas accretion can self-regulate.Methods. We have used the Atacama Large Millimeter Array (ALMA) to map the emission of a set of dense molecular gas (n(H2) ' 1056 cm3) tracers (CO(3-2), CO(6-5), HCN(4-3), HCO+(4-3), and CS(7-6)) and their underlying continuum emission in the central r ∼ 2 kpc of NGC 1068 with spatial resolutions ∼0:3000:500 (∼20-35 pc for the assumed distance of D = 14 Mpc). Results. The sensitivity and spatial resolution of ALMA give an unprecedented detailed view of the distribution and kinematics of the dense molecular gas (n(H2) ≈ 1056cm3) in NGC 1068. Molecular line and dust continuum emissions are detected from a r ∼ 200 pc off-centered circumnuclear disk (CND), from the 2.6 kpc-diameter bar region, and from the r ∼ 1:3 kpc starburst (SB) ring. Most of the emission in HCO+, HCN, and CS stems from the CND. Molecular line ratios show dramatic order-of-magnitude changes inside the CND that are correlated with the UV/X-ray illumination by the active galactic nucleus (AGN), betraying ongoing feedback. We used the dust continuum fluxes measured by ALMA together with NIR/MIR data to constrain the properties of the putative torus using CLUMPY models and found a torus radius of 20+6 10 pc. The Fourier decomposition of the gas velocity field indicates that rotation is perturbed by an inward radial flow in the SB ring and the bar region. However, the gas kinematics from r ∼ 50 pc out to r ∼ 400 pc reveal a massive (Mmol ∼ 2:7+0:9 1:2 × 107 M) outflow in all molecular tracers. The tight correlation between the ionized gas outflow, the radio jet, and the occurrence of outward motions in the disk suggests that the outflow is AGN driven. Conclusions. The molecular outflow is likely launched when the ionization cone of the narrow line region sweeps the nuclear disk. The outflow rate estimated in the CND, dM=dt ∼ 63+21 37 M yr1, is an order of magnitude higher than the star formation rate at these radii, confirming that the outflow is AGN driven. The power of the AGN is able to account for the estimated momentum and kinetic luminosity of the outflow. The CND mass load rate of the CND outflow implies a very short gas depletion timescale of ≤1 Myr. The CND gas reservoir is likely replenished on longer timescales by efficient gas inflow from the outer disk. © ESO 2014.
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| 15. |
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| 16. |
- Kankare, E., et al.
(author)
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DISCOVERY OF TWO SUPERNOVAE IN THE NUCLEAR REGIONS OF THE LUMINOUS INFRARED GALAXY IC 883
- 2012
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In: Astrophysical Journal Letters. - 2041-8205 .- 2041-8213. ; 744:2
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Journal article (peer-reviewed)abstract
- We report the discovery of two consecutive supernovae (SNe), 2010cu and 2011hi, located at 0 ''.37 (180 pc) and 0 ''.79 (380 pc) projected distance, respectively, from the center of the K-band nucleus of the luminous infrared galaxy (LIRG) IC 883. The SNe were discovered in an ongoing near-infrared K-band search for core-collapse SNe in such galaxies using the ALTAIR/NIRI adaptive optics system with laser guide star at the Gemini-North Telescope. These are thus the closest SNe yet discovered to an LIRG nucleus in optical or near-infrared wavelengths. The near-infrared light curves and colors of both SNe are consistent with core-collapse events. Both SNe seem to suffer from relatively low host galaxy extinction suggesting that regardless of their low projected galactocentric distances, they are not deeply buried in the nuclear regions of the host galaxy.
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| 17. |
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| 18. |
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| 19. |
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| 20. |
- Mattila, S., et al.
(author)
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Core collapse supernovae missed by optical surveys
- 2012
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In: Astrophysical Journal. - 0004-637X .- 1538-4357. ; 756:2, s. 111-
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Journal article (peer-reviewed)abstract
- We estimate the fraction of core-collapse supernovae (CCSNe) that remain undetected by optical SN searches due to obscuration by large amounts of dust in their host galaxies. This effect is especially important in luminous and ultraluminous infrared galaxies, which are locally rare but dominate the star formation at redshifts of z similar to 1-2. We perform a detailed investigation of the SN activity in the nearby luminous infrared galaxy Arp 299 and estimate that up to 83% of the SNe in Arp 299 and in similar galaxies in the local universe are missed by observations at optical wavelengths. For rest-frame optical surveys we find the fraction of SNe missed due to high dust extinction to increase from the average local value of similar to 19% to similar to 38% at z similar to 1.2 and then remain roughly constant up to z similar to 2. It is therefore crucial to take into account the effects of obscuration by dust when determining SN rates at high redshift and when predicting the number of CCSNe detectable by future high-z surveys such as LSST, JWST, and Euclid. For a sample of nearby CCSNe (distances 6-15 Mpc) detected during the last 12 yr, we find a lower limit for the local CCSN rate of 1.5(-0.3)(+0.4) x 10(-4) yr(-1) Mpc(-3), consistent with that expected from the star formation rate. Even closer, at distances less than similar to 6 Mpc, we find a significant increase in the CCSN rate, indicating a local overdensity of star formation caused by a small number of galaxies that have each hosted multiple SNe.
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