The distribution of interstellar dust in CALIFA edge-on galaxies via oligochromatic radiative transfer fitting

We investigate the amount and spatial distribution of interstellar dust in edge-on spiral galaxies, using detailed radiative transfer modeling of a homogeneous sample of 12 galaxies selected from the CALIFA survey. Our automated fitting routine, FitSKIRT, was first validated against artificial data. This is done by simultaneously reproducing the SDSS $g$-, $r$-, $i$- and $z$-band observations of a toy model in order to combine the information present in the different bands. We show that this combined, oligochromatic fitting, has clear advantages over standard monochromatic fitting especially regarding constraints on the dust properties. We model all galaxies in our sample using a three-component model, consisting of a double exponential disc to describe the stellar and dust discs and using a S\'ersic profile to describe the central bulge. The full model contains 19 free parameters, and we are able to constrain all these parameters to a satisfactory level of accuracy without human intervention or strong boundary conditions. Apart from two galaxies, the entire sample can be accurately reproduced by our model. We find that the dust disc is about 75% more extended but only half as high as the stellar disc. The average face-on optical depth in the V-band is $0.76$ and the spread of $0.60$ within our sample is quite substantial, which indicates that some spiral galaxies are relatively opaque even when seen face-on.Comment: 18 pages, 6 figures, 4 tables, Accepted for publication in MNRA

Identification and characterization of copy number variations in cattle

Copy number variations (CNVs) are an important source of genetic changes. They are defined as a gain or loss of genomic region ranging from 50 bp to several megabases. CNVs have been shown to be associated with many diseases and some phenotypic traits in several species, including cattle. We used Pindel, Delly, BreakDancer, and CNVnator to identify CNVs using whole-genome sequencing data of 200 animals from eight French dairy and beef cattle breeds. We selected only deletions and duplications predicted by at least two tools and present in at least two animals. We identified a total of 29,132 autosomal deletions and duplications which cover between 31 to 34% (784 to 865 Mb) of the autosomal genome, with an average of 6,000 events per animal. Among these deletions and duplications, 27,690 were present in at least two animals. Out of theses, 26,417 events were deletions, 674 were duplications and 599 regions were both (deletion and duplication within the same region). We defined a CNV as deletion and duplication in the same region, and we termed this region as CNV-Region (CNVR). The size of CNVRs ranged from 100 bp to 9.3 Mb with a median of 1.3 kb and a mean of 45 kb. From the identified deletions and duplications, 8,283 overlapped with 9,733 annotated genes including 290 CNVRs overlapping with 974 annotated genes, including some genes known to be implicated in some traits of economic importance. Our study provides an extensive view of the CNVRs in French dairy and beef breeds. CNVRs with an effect on some commercially interesting phenotypes could be used to improve genetic selection of these eight French breeds

Reproductive Technologies and Genomic Selection in Cattle

The recent development of genomic selection induces dramatic changes in the way genetic selection schemes are to be conducted. This review describes the new context and corresponding needs for genomic based selection schemes and how reproductive technologies can be used to meet those needs. Information brought by reproductive physiology will provide new markers and new improved phenotypes that will increase the efficiency of selection schemes for reproductive traits. In this context, the value of the reproductive techniques including assisted embryo based reproductive technologies (Multiple Ovaluation Embryo Transfer and Ovum pick up associated to in vitro Fertilization) is also revisited. The interest of embryo typing is discussed. The recent results obtained with this emerging technology which are compatible with the use of the last generation of chips for genotype analysis may lead to very promising applications for the breeding industry. The combined use of several embryo based reproductive technologies will probably be more important in the near future to satisfy the needs of genomic selection for increasing the number of candidates and to preserve at the same time genetic variability

The dust-star interplay in late-type galaxies at z < 0.5: Forecasts for the JWST

Context. In recent years, significant growth in the amount of data available to astronomers has opened up the possibility for extensive multi-wavelength approaches. In the field of galaxy evolution, such approaches have uncovered fundamental correlations, linking the dust component of a galaxy to its star formation rate (SFR). Despite these achievements, the relation between the SFR and the dust is still challenging, with uncertainties related to the physical mechanisms linking the two. Aims: In this paper, we re-examine these correlations, paying specific attention to the intrinsic properties of the dust. Our goal is to investigate the origin of the observed scatter in low-redshift galaxies, and the ability of the James Webb Space Telescope (JWST) to explore such relations in the early Universe. Methods: We defined a sample of about 800 normal star-forming galaxies with photometries in the range of 0.15 Results: Dust luminosity (Ld) and SFR show a strong correlation, but for SFR ⊙ yr−1, the correlation scatter increases dramatically. We show that selection based on the fraction of ultraviolet (UV) emission absorbed by dust, that is, the UV extinction, greatly reduces the data dispersion. Dust masses (Md) and SFR show a weaker correlation, with a larger scatter due to the interstellar radiation field produced by stars during late evolutionary stages, which shifts the positions of the galaxies in the dust mass-SFR plane. At z = 2, more than 60% of the galaxies in the sample are detected with F770, F1000, F1280, F1500, and F1800. At higher redshifts, the detection decreases, and only 45% of z = 8 galaxies are detected with two filters. Reproducing the expected sensitivity of the Cosmic Evolution Early Release Science Survey and classifying galaxies according to their SFR and stellar mass (M*), we investigated the MIRI detection rate as a function of the physical properties of the galaxies. Fifty percent of the objects with SFR ∼ 1 M⊙ yr−1 at z = 6 are detected with F770, which decreases to 20% at z = 8. For such galaxies, only 5% of the subsample will be detected at 5σ with F770 and F1000 at z = 8, and only 10% with F770, F1000, and F1280 at z = 6. For galaxies with higher SFR, detection with these three filters will be possible up to z = 6 in ∼60% of the subsample. Conclusions: The link between dust and star formation is complex, and many aspects remain to be fully understood. The scatter between SFR and dust mass, and SFR and luminosity, decreases significantly when the analysis includes dust properties. In this context, the JWST will revolutionise the field, allowing investigation of the dust-star interplay well within the epoch of reionisation

The Herschel Virgo Cluster Survey XIX. Physical properties of low luminosity FIR sources at z < 0.5

Context. The star formation rate is a crucial parameter for the investigation galaxy evolution. At low redshift the cosmic star formation rate density declines smoothly, and massive active galaxies become passive, reducing their star formation activity. This implies that the bulk of the star formation rate density at low redshift is mainly driven by low mass objects. Aims. We investigate the properties of a sample of low luminosity far-infrared sources selected at 250 μm. We have collected data from ultraviolet to far-infrared in order to perform a multiwavelengths analysis. The main goal is to investigate the correlation between star formation rate, stellar mass, and dust mass for a galaxy population with a wide range in dust content and stellar mass, including the low mass regime that most probably dominates the star formation rate density at low redshift. Methods. We define a main sample of ~800 sources with full spectral energy distribution coverage between 0.15 <λ< 500 μm and an extended sample with ~5000 sources in which we remove the constraints on the ultraviolet and near-infrared bands. We analyze both samples with two different spectral energy distribution fitting methods: MAGPHYS and CIGALE, which interpret a galaxy spectral energy distribution as a combination of different simple stellar population libraries and dust emission templates. Results. In the star formation rate versus stellar mass plane our samples occupy a region included between local spirals and higher redshift star forming galaxies. These galaxies represent the population that at z 3 × 1010 M⊙) do not lie on the main sequence, but show a small offset as a consequence of the decreased star formation. Low mass galaxies (M∗< 1 × 1010 M⊙) settle in the main sequence with star formation rate and stellar mass consistent with local spirals. Conclusions. Deep Herschel data allow the identification of a mixed galaxy population with galaxies still in an assembly phase or galaxies at the beginning of their passive evolution. We find that the dust luminosity is the parameter that allow us to discriminate between these two galaxy populations. The median spectral energy distribution shows that even at low star formation rate our galaxy sample has a higher mid-infrared emission than previously predicted

High-resolution, 3D radiative transfer modeling: I. The grand-design spiral galaxy M 51

International audienceContext. Dust reprocesses about half of the stellar radiation in galaxies. The thermal re-emission by dust of absorbed energy is considered to be driven merely by young stars so is often applied to tracing the star formation rate in galaxies. Recent studies have argued that the old stellar population might be responsible for a non-negligible fraction of the radiative dust heating.Aims. In this work, we aim to analyze the contribution of young (≲100 Myr) and old (~10 Gyr) stellar populations to radiative dust heating processes in the nearby grand-design spiral galaxy M 51 using radiative transfer modeling. High-resolution 3D radiative transfer (RT) models are required to describe the complex morphologies of asymmetric spiral arms and clumpy star-forming regions and to model the propagation of light through a dusty medium. Methods. In this paper, we present a new technique developed to model the radiative transfer effects in nearby face-on galaxies. We construct a high-resolution 3D radiative transfer model with the Monte-Carlo code SKIRT to account for the absorption, scattering, and non-local thermal equilibrium (NLTE) emission of dust in M 51. The 3D distribution of stars is derived from the 2D morphology observed in the IRAC 3.6 μm, GALEX FUV, Hα, and MIPS 24 μm wavebands, assuming an exponential vertical distribution with an appropriate scale height. The dust geometry is constrained through the far-ultraviolet (FUV) attenuation, which is derived from the observed total-infrared-to-far-ultraviolet luminosity ratio. The stellar luminosity, star formation rate, and dust mass have been scaled to reproduce the observed stellar spectral energy distribution (SED), FUV attenuation, and infrared SED.Results. The dust emission derived from RT calculations is consistent with far-infrared and submillimeter observations of M 51, implying that the absorbed stellar energy is balanced by the thermal re-emission of dust. The young stars provide 63% of the energy for heating the dust responsible for the total infrared emission (8−1000 μm), while 37% of the dust emission is governed through heating by the evolved stellar population. In individual wavebands, the contribution from young stars to the dust heating dominates at all infrared wavebands but gradually decreases towards longer infrared and submillimeter wavebands for which the old stellar population becomes a non-negligible source of heating. Upon extrapolation of the results for M 51, we present prescriptions for estimating the contribution of young stars to the global dust heating based on a tight correlation between the dust heating fraction and specific star formation rate

C-Nap1 mutation affects centriole cohesion and is associated with a Seckel-like syndrome in cattle

Caprine-like Generalized Hypoplasia Syndrome (SHGC) is an autosomal-recessive disorder in Montbéliarde cattle. Affected animals present a wide range of clinical features that include the following: delayed development with low birth weight, hind limb muscular hypoplasia, caprine-like thin head and partial coat depigmentation. Here we show that SHGC is caused by a truncating mutation in the CEP250 gene that encodes the centrosomal protein C-Nap1. This mutation results in centrosome splitting, which neither affects centriole ultrastructure and duplication in dividing cells nor centriole function in cilium assembly and mitotic spindle organization. Loss of C-Nap1-mediated centriole cohesion leads to an altered cell migration phenotype. This discovery extends the range of loci that constitute the spectrum of autosomal primary recessive microcephaly (MCPH) and Seckel-like syndromes

FROM’MIR : Développer des outils de prédiction et de conseil pour maîtriser la fromageabilité des laits destinés à la fabrication des fromages traditionnels franc-comtois

Ce volume regroupe les textes issus du programme Casdar "Innovation et Partenariat" et "Recherche finalisée et innovation" de 2014. Il a été réalisé sous l’égide du GIS Relance Agronomique.Mid-infrared spectroscopy prediction equations of the cheese-making properties of milk, established inthe Franche-Comté PDO/PGI context, exist for the first time in France. Laboratory curd yield in DryMatter was consistent with the yields observed in mini-manufactures of soft and pressed cookedcheeses and it is the best predicted parameter. Under our conditions, some coagulation properties suchas curd firmness could be estimated. The acidification properties, which heavily depend on themicrobiological component of milk, are poorly estimated. The best prediction performances wereobtained on individual cow milks. The performances were poorer on the scale of bulk milks, herd tankmilk but especially dairy vat milk. The study of variation factors made it possible to highlight theimportant weight of genetics with a high level of heritability and strong effects of the genome regionsinvolved. The quality and quantity of fodder and the distribution of calves were influential in the contextstudied. In this same context, few factors of variation have been identified at the scale of dairy vat milks,as the practices were very much governed by the PDO specifications. At the end of this project, anobservatory, from the quality of the milk to the quality of the cheese, will be set up in Franche Comté.Studies will also be carried out at the national level to consolidate and improve the equations in othercontexts.Des équations MIR (spectrométrie moyen infrarouge) d'estimation de la fromageabilité des laits,établies en contexte AOP/IGP franc-comtois, existent pour la première fois en France. Le rendementlaboratoire extrait sec (ES), cohérent avec les rendements observés en mini-fabrications de fromages àpâte molle et à pâte pressée cuite, est le paramètre le mieux prédit. Dans nos conditions, certainsaspects de l'aptitude à la coagulation enzymatique, comme la fermeté des gels, peuvent être estimés.L’aptitude à l’acidification, dépendant fortement de la composante microbiologique des laits, est quant àelle mal estimée. Les meilleures performances de prédiction sont obtenues sur les laits individuels devaches. Les performances sont moins bonnes à l’échelle des laits de mélange, des laits de troupeauxmais surtout des laits de cuves de fromagerie. L'étude des facteurs de variation a permis de mettre enévidence le poids important de la génétique avec un niveau d’héritabilité élevé et des effets forts desrégions du génome impliquées. La qualité et la quantité de fourrages ainsi que la répartition desvêlages sont influents dans le contexte étudié. Dans ce même contexte, peu de facteurs de variationont été mis en évidence à l’échelle des laits de cuves, les pratiques étant très encadrées par le cahierdes charges AOP. A l’issue de ce projet, un observatoire, depuis la qualité des laits jusqu’à celle desfromages, va être mis en place en Franche Comté. Des études seront aussi mises en œuvre au niveaunational pour permettre notamment une consolidation et une amélioration des équations dans d'autrescontextes

16p11.2 600 kb Duplications confer risk for typical and atypical Rolandic epilepsy

Rolandic epilepsy (RE) is the most common idiopathic focal childhood epilepsy. Its molecular basis is largely unknown and a complex genetic etiology is assumed in the majority of affected individuals. The present study tested whether six large recurrent copy number variants at 1q21, 15q11.2, 15q13.3, 16p11.2, 16p13.11 and 22q11.2 previously associated with neurodevelopmental disorders also increase risk of RE. Our association analyses revealed a significant excess of the 600 kb genomic duplication at the 16p11.2 locus (chr16: 29.5-30.1 Mb) in 393 unrelated patients with typical (n = 339) and atypical (ARE; n = 54) RE compared with the prevalence in 65 046 European population controls (5/393 cases versus 32/65 046 controls; Fisher's exact test P = 2.83 × 10−6, odds ratio = 26.2, 95% confidence interval: 7.9-68.2). In contrast, the 16p11.2 duplication was not detected in 1738 European epilepsy patients with either temporal lobe epilepsy (n = 330) and genetic generalized epilepsies (n = 1408), suggesting a selective enrichment of the 16p11.2 duplication in idiopathic focal childhood epilepsies (Fisher's exact test P = 2.1 × 10−4). In a subsequent screen among children carrying the 16p11.2 600 kb rearrangement we identified three patients with RE-spectrum epilepsies in 117 duplication carriers (2.6%) but none in 202 carriers of the reciprocal deletion. Our results suggest that the 16p11.2 duplication represents a significant genetic risk factor for typical and atypical R