189 research outputs found
Varieties and seeds for organic farming: a solution for cabbage through participatory breeding in Brittany
In partnership with INRA, professionals from the organic vegetable sector in Brittany conducted a breeding programme for organically-farmed cabbage based on an evaluation programme of genetic resources collected from French (INRA) and European gene banks at the PAIS (Agro-biological platform of the Interprofessional Association for Organic Farming in Brittany), located in Suscinio. Between 2001 and 2003, the evaluation focused on quality criteria for commercial products and the suitability of varieties to the organic market, as well as on their adaptation to the environment. About 400 populations of cauliflower have thus been evaluated at the PAIS and/or by professionals in the sector in Brittany in order to evaluate their adaptation to organic production under different soil conditions and their suitability to various marketing channels. Ten of them were selected. Focused at first on cabbage, the programme was extended at the request of professionals and led to the breeding of several other species (tomato, carrot, lettuce, spinach, etc.). Breeding programs must now be optimized in order to satisfy consumer quality and adaptability requirements, and to design a coherent regulatory framework for participatory plant breeding and organic farming
The VIPERS Multi-Lambda Survey. I. UV and NIR Observations, multi-color catalogues and photometric redshifts
We present observations collected in the CFHTLS-VIPERS region in the
ultraviolet (UV) with the GALEX satellite (far and near UV channels) and the
near infrared with the CFHT/WIRCam camera (-band) over an area of 22 and
27 deg, respectively. The depth of the photometry was optimized to measure
the physical properties (e.g., SFR, stellar masses) of all the galaxies in the
VIPERS spectroscopic survey. The large volume explored by VIPERS will enable a
unique investigation of the relationship between the galaxy properties and
their environment (density field and cosmic web) at high redshift (0.5 < z <
1.2). In this paper, we present the observations, the data reductions and the
build-up of the multi-color catalogues. The CFHTLS-T0007 (gri-{\chi}^2) images
are used as reference to detect and measure the -band photometry, while
the T0007 u-selected sources are used as priors to perform the GALEX photometry
based on a dedicated software (EMphot). Our final sample reaches ~25
(at 5{\sigma}) and ~22 (at 3{\sigma}). The large spectroscopic sample
(~51,000 spectroscopic redshifts) allows us to highlight the robustness of our
star/galaxy separation, and the reliability of our photometric redshifts with a
typical accuracy 0.04 and a catastrophic failure rate {\eta} <
2% down to i~23. We present various tests on the band completeness and
photometric redshift accuracy by comparing with existing, overlapping deep
photometric catalogues. Finally, we discuss the BzK sample of passive and
active galaxies at high redshift and the evolution of galaxy morphology in the
(NUV-r) vs (r-K_s) diagram at low redshift (z < 0.25) thanks to the high image
quality of the CFHTLS. The images, catalogues and photometric redshifts for 1.5
million sources (down to 25 or 22) are released and
available at this URL: http://cesam.lam.fr/vipers-mls/Comment: 14 pages, 16 figures. Accepted for publication in A&A. Version to be
publishe
ASASSN-15lh: A Highly Super-Luminous Supernova
We report the discovery of ASASSN-15lh (SN 2015L), which we interpret as the
most luminous supernova yet found. At redshift z = 0.2326, ASASSN-15lh reached
an absolute magnitude of M_{u,AB} = -23.5+/-0.1 and bolometric luminosity L_bol
= (2.2+/-0.2)x 10^45 ergs s^-1, which is more than twice as luminous as any
previously known supernova. It has several major features characteristic of the
hydrogen-poor super-luminous supernovae (SLSNe-I), whose energy sources and
progenitors are currently poorly understood. In contrast to most previously
known SLSNe-I that reside in star-forming dwarf galaxies, ASASSN-15lh appears
to be hosted by a luminous galaxy (M_K ~ -25.5) with little star formation. In
the 4 months since first detection, ASASSN-15lh radiated (1.1+/- 0.2)x10^52
ergs, challenging the magnetar model for its engine.Comment: Published in the January 15, 2016 Issue of Science Magazin
Recovery and analysis of rest-frame UV emission lines in 2052 galaxies observed with MUSE at 1.5 < z < 6.4
Rest-frame ultraviolet (UV) emission lines probe electron densities, gas-phase abundances, metallicities, and ionization parameters of the emitting star-forming galaxies and their environments. The strongest main UV emission line, Lyα, has been instrumental in advancing the general knowledge of galaxy formation in the early universe. However, observing Lyα emission becomes increasingly challenging at zââłâ6 when the neutral hydrogen fraction of the circumgalactic and intergalactic media increases. Secondary weaker UV emission lines provide important alternative methods for studying galaxy properties at high redshift. We present a large sample of rest-frame UV emission line sources at intermediate redshift for calibrating and exploring the connection between secondary UV lines and the emitting galaxiesâ physical properties and their Lyα emission. The sample of 2052 emission line sources with 1.5â<âzâ<â6.4 was collected from integral field data from the MUSE-Wide and MUSE-Deep surveys taken as part of Guaranteed Time Observations. The objects were selected through untargeted source detection (i.e., no preselection of sources as in dedicated spectroscopic campaigns) in the three-dimensional MUSE data cubes. We searched optimally extracted one-dimensional spectra of the full sample for UV emission features via emission line template matching, resulting in a sample of more than 100 rest-frame UV emission line detections. We show that the detection efficiency of (non-Lyα) UV emission lines increases with survey depth, and that the emission line strength of HeâŻIIλ1640 Ă
, [OâŻIII] λ1661 + OâŻIII] λ1666, and [SiâŻIII] λ1883 + SiâŻIII] λ1892 correlate with the strength of [CâŻIII] λ1907 + CâŻIII] λ1909. The rest-frame equivalent width (EW0) of [CâŻIII] λ1907 + CâŻIII] λ1909 is found to be roughly 0.22 ± 0.18 of EW0(Lyα). We measured the velocity offsets of resonant emission lines with respect to systemic tracers. For CâŻIVλ1548 + CâŻIVλ1551 we find that ÎvCâŻIV âČ 250 km sâ1, whereas ÎvLyα falls in the range of 250â500 km sâ1 which is in agreement with previous results from the literature. The electron density ne measured from [SiâŻIII] λ1883 + SiâŻIII] λ1892 and [CâŻIII] λ1907 + CâŻIII] λ1909 line flux ratios is generally < 105 cmâ3 and the gas-phase abundance is below solar at 12â
+â
log10(O/H)â8. Lastly, we used âPhotoIonization Model Probability Density Functionsâ to infer physical parameters of the full sample and individual systems based on photoionization model parameter grids and observational constraints from our UV emission line searches. This reveals that the UV line emitters generally have ionization parameter log10(U)ââââ2.5 and metal mass fractions that scatter around Zâââ10â2, that is Zâââ0.66âZâ. Value-added catalogs of the full sample of MUSE objects studied in this work and a collection of UV line emitters from the literature are provided with this paper
The Astropy Project: Building an Open-science Project and Status of the v2.0 Core Package
The Astropy Project supports and fosters the development of open-source and openly developed Python packages that provide commonly needed functionality to the astronomical community. A key element of the Astropy Project is the core package astropy, which serves as the foundation for more specialized projects and packages. In this article, we provide an overview of the organization of the Astropy project and summarize key features in the core package, as of the recent major release, version 2.0. We then describe the project infrastructure designed to facilitate and support development for a broader ecosystem of interoperable packages. We conclude with a future outlook of planned new features and directions for the broader Astropy Project
Astropy: A Community Python Package for Astronomy
We present the first public version (v0.2) of the open-source and community-developed Python package, Astropy. This package provides core astronomy-related functionality to the community, including support for domain-specific file formats such as Flexible Image Transport System (FITS) files, Virtual Observatory (VO) tables, and common ASCII table formats, unit and physical quantity conversions, physical constants specific to astronomy, celestial coordinate and time transformations, world coordinate system (WCS) support, generalized containers for representing gridded as well as tabular data, and a framework for cosmological transformations and conversions. Significant functionality is under active development, such as a model fitting framework, VO client and server tools, and aperture and point spread function (PSF) photometry tools. The core development team is actively making additions and enhancements to the current code base, and we encourage anyone interested to participate in the development of future Astropy versions
The ASAS-SN Bright Supernova Catalog I: 2013-2014
We present basic statistics for all supernovae discovered by the All-Sky Automated Survey for SuperNovae (ASAS-SN) during its first year-and-a-half of operations, spanning 2013 and 2014. We also present the same information for all other bright (), spectroscopically confirmed supernovae discovered from 2014 May 1 through the end of 2014, providing a comparison to the ASAS-SN sample starting from the point where ASAS-SN became operational in both hemispheres. In addition, we present collected redshifts and near-UV through IR magnitudes, where available, for all host galaxies of the bright supernovae in both samples. This work represents a comprehensive catalog of bright supernovae and their hosts from multiple professional and amateur sources, allowing for population studies that were not previously possible because the all-sky emphasis of ASAS-SN redresses most previously existing biases. In particular, ASAS-SN systematically finds supernovae closer to the centers of host galaxies than either other professional surveys or amateurs, a remarkable result given ASAS-SN's poorer angular resolution. This is the first of a series of yearly papers on bright supernovae and their hosts that will be released by the ASAS-SN team
The First Illumina-Based De Novo Transcriptome Sequencing and Analysis of Safflower Flowers
BACKGROUND: The safflower, Carthamus tinctorius L., is a worldwide oil crop, and its flowers, which have a high flavonoid content, are an important medicinal resource against cardiovascular disease in traditional medicine. Because the safflower has a large and complex genome, the development of its genomic resources has been delayed. Second-generation Illumina sequencing is now an efficient route for generating an enormous volume of sequences that can represent a large number of genes and their expression levels. METHODOLOGY/PRINCIPAL FINDINGS: To investigate the genes and pathways that might control flavonoids and other secondary metabolites in the safflower, we used Illumina sequencing to perform a de novo assembly of the safflower tubular flower tissue transcriptome. We obtained a total of 4.69 Gb in clean nucleotides comprising 52,119,104 clean sequencing reads, 195,320 contigs, and 120,778 unigenes. Based on similarity searches with known proteins, we annotated 70,342 of the unigenes (about 58% of the identified unigenes) with cut-off E-values of 10(-5). In total, 21,943 of the safflower unigenes were found to have COG classifications, and BLAST2GO assigned 26,332 of the unigenes to 1,754 GO term annotations. In addition, we assigned 30,203 of the unigenes to 121 KEGG pathways. When we focused on genes identified as contributing to flavonoid biosynthesis and the biosynthesis of unsaturated fatty acids, which are important pathways that control flower and seed quality, respectively, we found that these genes were fairly well conserved in the safflower genome compared to those of other plants. CONCLUSIONS/SIGNIFICANCE: Our study provides abundant genomic data for Carthamus tinctorius L. and offers comprehensive sequence resources for studying the safflower. We believe that these transcriptome datasets will serve as an important public information platform to accelerate studies of the safflower genome, and may help us define the mechanisms of flower tissue-specific and secondary metabolism in this non-model plant
A Systematic Study of Mid-Infrared Emission from Core-Collapse Supernovae with Spirits
The American Astronomical Society. All rights reserved.We present a systematic study of mid-infrared emission from 141 nearby supernovae (SNe) observed with Spitzer/IRAC as part of the ongoing SPIRITS survey. We detect 8 Type Ia and 36 core-collapse SNe. All Type Ia/Ibc SNe become undetectable within three years of explosion, whereas 22 ± 11% of Type II SNe continue to be detected. Five Type II SNe are detected even two decades after discovery (SN 1974E, 1979C, 1980K, 1986J, and 1993J). Warm dust luminosity, temperature, and a lower limit on mass are obtained by fitting the two IRAC bands, assuming an optically thin dust shell. We derive warm dust masses between 10-6 and 10-2 M o and dust color temperatures between 200 and 1280 K. This observed warm dust could be pre-existing or newly created, but in either case represents a lower limit to the dust mass because cooler dust may be present. We present three case studies of extreme SNe. SN 2011ja (II-P) was over-luminous ([4.5] = -15.6 mag) at 900 days post explosion with increasing hot dust mass, suggesting either an episode of dust formation or intensifying circumstellar material (CSM) interactions heating up pre-existing dust. SN 2014bi (II-P) showed a factor of 10 decrease in dust mass over one month, suggesting either dust destruction or reduced dust heating. The IR luminosity of SN 2014C (Ib) stayed constant over 800 days, possibly due to strong CSM interaction with an H-rich shell, which is rare among stripped-envelope SNe. The observations suggest that this CSM shell originated from an LBV-like eruption roughly 100 years pre-explosion. The observed diversity demonstrates the power of mid-IR observations of a large sample of SNe. © 2017
Evaluation and mangement of fungal risk in cystic fibrosis: first results of a national French study
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