Multiply lensed images of a same source experience a relative time delay in the arrival of photons due to the path length difference and the different gravitational potentials the photons travel ...through. This effect can be used to measure absolute distances and the Hubble constant (
H
0
) and is known as time-delay cosmography. The method is independent of the local distance ladder and early-universe physics and provides a precise and competitive measurement of
H
0
. With upcoming observatories, time-delay cosmography can provide a 1% precision measurement of
H
0
and can decisively shed light on the current reported ‘Hubble tension’. This manuscript details the general methodology developed over the past decades in time-delay cosmography, discusses recent advances and results, and, foremost, provides a foundation and outlook for the next decade in providing accurate and ever more precise measurements with increased sample size and improved observational techniques.
Since echinocandins are recommended as first line therapy for invasive candidiasis, detection of resistance, mainly due to alteration in FKS protein, is of main interest. EUCAST AFST recommends ...testing both MIC of anidulafungin and micafungin, and breakpoints (BPs) have been proposed to detect echinocandin-resistant isolates. We analyzed MIC distribution for all three available echinocandins of 2,787 clinical yeast isolates corresponding to 5 common and 16 rare yeast species, using the standardized EUCAST method for anidulafungin and modified for caspofungin and micafungin (AM3-MIC). In our database, 64 isolates of common pathogenic species were resistant to anidulafungin, according to the EUCAST BP, and/or to caspofungin, using our previously published threshold (AM3-MIC ≥ 0.5 mg/L). Among these 64 isolates, 50 exhibited 21 different FKS mutations. We analyzed the capacity of caspofungin AM3-MIC and anidulafungin MIC determination in detecting isolates with FKS mutation. They were always identified using caspofungin AM3-MIC and the local threshold while some isolates were misclassified using anidulafungin MIC and EUCAST threshold. However, both methods misclassified four wild-type C. glabrata as resistant. Based on a large data set from a single center, the use of AM3-MIC testing for caspofungin looks promising in identifying non-wild-type C. albicans, C. tropicalis and P. kudiravzevii isolates, but additional multicenter comparison is mandatory to conclude on the possible superiority of AM3-MIC testing compared to the EUCAST method.
TDCOSMO Birrer, S; Shajib, A J; Galan, A ...
Astronomy & astrophysics,
11/2020, Letnik:
643
Journal Article
Recenzirano
Odprti dostop
The H0LiCOW collaboration inferred via strong gravitational lensing time delays a Hubble constant value of H0 = 73.3−1.8+1.7 km s−1 Mpc−1, describing deflector mass density profiles by either a ...power-law or stars (constant mass-to-light ratio) plus standard dark matter halos. The mass-sheet transform (MST) that leaves the lensing observables unchanged is considered the dominant source of residual uncertainty in H0. We quantify any potential effect of the MST with a flexible family of mass models, which directly encodes it, and they are hence maximally degenerate with H0. Our calculation is based on a new hierarchical Bayesian approach in which the MST is only constrained by stellar kinematics. The approach is validated on mock lenses, which are generated from hydrodynamic simulations. We first applied the inference to the TDCOSMO sample of seven lenses, six of which are from H0LiCOW, and measured H0 = 74.5−6.1+5.6 km s−1 Mpc−1. Secondly, in order to further constrain the deflector mass density profiles, we added imaging and spectroscopy for a set of 33 strong gravitational lenses from the Sloan Lens ACS (SLACS) sample. For nine of the 33 SLAC lenses, we used resolved kinematics to constrain the stellar anisotropy. From the joint hierarchical analysis of the TDCOSMO+SLACS sample, we measured H0 = 67.4−3.2+4.1 km s−1 Mpc−1. This measurement assumes that the TDCOSMO and SLACS galaxies are drawn from the same parent population. The blind H0LiCOW, TDCOSMO-only and TDCOSMO+SLACS analyses are in mutual statistical agreement. The TDCOSMO+SLACS analysis prefers marginally shallower mass profiles than H0LiCOW or TDCOSMO-only. Without relying on the form of the mass density profile used by H0LiCOW, we achieve a ∼5% measurement of H0. While our new hierarchical analysis does not statistically invalidate the mass profile assumptions by H0LiCOW – and thus the H0 measurement relying on them – it demonstrates the importance of understanding the mass density profile of elliptical galaxies. The uncertainties on H0 derived in this paper can be reduced by physical or observational priors on the form of the mass profile, or by additional data.
TDCOSMO Millon, M; Galan, A; Courbin, F ...
Astronomy & astrophysics,
07/2020, Letnik:
639
Journal Article
Recenzirano
Odprti dostop
Time-delay cosmography of lensed quasars has achieved 2.4% precision on the measurement of the Hubble constant, H0. As part of an ongoing effort to uncover and control systematic uncertainties, we ...investigate three potential sources: 1- stellar kinematics, 2- line-of-sight effects, and 3- the deflector mass model. To meet this goal in a quantitative way, we reproduced the H0LiCOW/SHARP/STRIDES (hereafter TDCOSMO) procedures on a set of real and simulated data, and we find the following. First, stellar kinematics cannot be a dominant source of error or bias since we find that a systematic change of 10% of measured velocity dispersion leads to only a 0.7% shift on H0 from the seven lenses analyzed by TDCOSMO. Second, we find no bias to arise from incorrect estimation of the line-of-sight effects. Third, we show that elliptical composite (stars + dark matter halo), power-law, and cored power-law mass profiles have the flexibility to yield a broad range in H0 values. However, the TDCOSMO procedures that model the data with both composite and power-law mass profiles are informative. If the models agree, as we observe in real systems owing to the “bulge-halo” conspiracy, H0 is recovered precisely and accurately by both models. If the two models disagree, as in the case of some pathological models illustrated here, the TDCOSMO procedure either discriminates between them through the goodness of fit, or it accounts for the discrepancy in the final error bars provided by the analysis. This conclusion is consistent with a reanalysis of six of the TDCOSMO (real) lenses: the composite model yields H0 = 74.0−1.8+1.7 km s−1 Mpc−1, while the power-law model yields 74.2−1.6+1.6 km s−1 Mpc−1. In conclusion, we find no evidence of bias or errors larger than the current statistical uncertainties reported by TDCOSMO.
TDCOSMO Birrer, S.; Shajib, A. J.; Galan, A. ...
Astronomy and astrophysics (Berlin),
11/2020, Letnik:
643
Journal Article, Web Resource
Recenzirano
Odprti dostop
The H0LiCOW collaboration inferred via strong gravitational lensing time delays a Hubble constant value of
H
0
= 73.3
−1.8
+1.7
km s
−1
Mpc
−1
, describing deflector mass density profiles by either a ...power-law or stars (constant mass-to-light ratio) plus standard dark matter halos. The mass-sheet transform (MST) that leaves the lensing observables unchanged is considered the dominant source of residual uncertainty in
H
0
. We quantify any potential effect of the MST with a flexible family of mass models, which directly encodes it, and they are hence maximally degenerate with
H
0
. Our calculation is based on a new hierarchical Bayesian approach in which the MST is only constrained by stellar kinematics. The approach is validated on mock lenses, which are generated from hydrodynamic simulations. We first applied the inference to the TDCOSMO sample of seven lenses, six of which are from H0LiCOW, and measured
H
0
= 74.5
−6.1
+5.6
km s
−1
Mpc
−1
. Secondly, in order to further constrain the deflector mass density profiles, we added imaging and spectroscopy for a set of 33 strong gravitational lenses from the Sloan Lens ACS (SLACS) sample. For nine of the 33 SLAC lenses, we used resolved kinematics to constrain the stellar anisotropy. From the joint hierarchical analysis of the TDCOSMO+SLACS sample, we measured
H
0
= 67.4
−3.2
+4.1
km s
−1
Mpc
−1
. This measurement assumes that the TDCOSMO and SLACS galaxies are drawn from the same parent population. The blind H0LiCOW, TDCOSMO-only and TDCOSMO+SLACS analyses are in mutual statistical agreement. The TDCOSMO+SLACS analysis prefers marginally shallower mass profiles than H0LiCOW or TDCOSMO-only. Without relying on the form of the mass density profile used by H0LiCOW, we achieve a ∼5% measurement of
H
0
. While our new hierarchical analysis does not statistically invalidate the mass profile assumptions by H0LiCOW – and thus the
H
0
measurement relying on them – it demonstrates the importance of understanding the mass density profile of elliptical galaxies. The uncertainties on
H
0
derived in this paper can be reduced by physical or observational priors on the form of the mass profile, or by additional data.
TDCOSMO Millon, M.; Galan, A.; Courbin, F. ...
Astronomy and astrophysics (Berlin),
07/2020, Letnik:
639
Journal Article, Web Resource
Recenzirano
Odprti dostop
Time-delay cosmography of lensed quasars has achieved 2.4% precision on the measurement of the Hubble constant,
H
0
. As part of an ongoing effort to uncover and control systematic uncertainties, we ...investigate three potential sources: 1- stellar kinematics, 2- line-of-sight effects, and 3- the deflector mass model. To meet this goal in a quantitative way, we reproduced the H0LiCOW/SHARP/STRIDES (hereafter TDCOSMO) procedures on a set of real and simulated data, and we find the following. First, stellar kinematics cannot be a dominant source of error or bias since we find that a systematic change of 10% of measured velocity dispersion leads to only a 0.7% shift on
H
0
from the seven lenses analyzed by TDCOSMO. Second, we find no bias to arise from incorrect estimation of the line-of-sight effects. Third, we show that elliptical composite (stars + dark matter halo), power-law, and cored power-law mass profiles have the flexibility to yield a broad range in
H
0
values. However, the TDCOSMO procedures that model the data with both composite and power-law mass profiles are informative. If the models agree, as we observe in real systems owing to the “bulge-halo” conspiracy,
H
0
is recovered precisely and accurately by both models. If the two models disagree, as in the case of some pathological models illustrated here, the TDCOSMO procedure either discriminates between them through the goodness of fit, or it accounts for the discrepancy in the final error bars provided by the analysis. This conclusion is consistent with a reanalysis of six of the TDCOSMO (real) lenses: the composite model yields
H
0
= 74.0
−1.8
+1.7
km s
−1
Mpc
−1
, while the power-law model yields 74.2
−1.6
+1.6
km s
−1
Mpc
−1
. In conclusion, we find no evidence of bias or errors larger than the current statistical uncertainties reported by TDCOSMO.
A comprehensive male linkage map was generated by adding 359 new, informative microsatellites to the International Equine Gene Map half-sibling reference families and by combining genotype data from ...three independent mapping resources: a full sibling family created at the Animal Health Trust in Newmarket, United Kingdom, eight half-sibling families from Sweden and two half-sibling families from the University of California, Davis. Because the combined data were derived primarily from half-sibling families, only autosomal markers were analyzed. The map was constructed from a total of 766 markers distributed on the 31 equine chromosomes. It has a higher marker density than that of previously reported maps, with 626 markers linearly ordered and 140 other markers assigned to a chromosomal region. Fifty-nine markers (7%) failed to meet the criteria for statistical evidence of linkage and remain unassigned. The map spans 3,740 cM with an average distance of 6.3 cM between markers. Fifty-five percent of the intervals are < or = 5 cM and only 3% > or = 20 cM. The present map demonstrates the cohesiveness of the different data sets and provides a single resource for genome scan analyses and integration with the radiation hybrid map.
A first-generation radiation hybrid (RH) map of the equine (Equus caballus) genome was assembled using 92 horse x hamster hybrid cell lines and 730 equine markers. The map is the first comprehensive ...framework map of the horse that (1) incorporates type I as well as type II markers, (2) integrates synteny, cytogenetic, and meiotic maps into a consensus map, and (3) provides the most detailed genome-wide information to date on the organization and comparative status of the equine genome. The 730 loci (258 type I and 472 type II) included in the final map are clustered in 101 RH groups distributed over all equine autosomes and the X chromosome. The overall marker retention frequency in the panel is approximately 21%, and the possibility of adding any new marker to the map is approximately 90%. On average, the mapped markers are distributed every 19 cR (4 Mb) of the equine genome--a significant improvement in resolution over previous maps. With 69 new FISH assignments, a total of 253 cytogenetically mapped loci physically anchor the RH map to various chromosomal segments. Synteny assignments of 39 gene loci complemented the RH mapping of 27 genes. The results added 12 new loci to the horse gene map. Lastly, comparison of the assembly of 447 equine genes (256 linearly ordered RH-mapped and additional 191 FISH-mapped) with the location of draft sequences of their human and mouse orthologs provides the most extensive horse-human and horse-mouse comparative map to date. We expect that the foundation established through this map will significantly facilitate rapid targeted expansion of the horse gene map and consequently, mapping and positional cloning of genes governing traits significant to the equine industry.
The current genetic and recombination maps of the cat have fewer than 3,000 markers and a resolution limit greater than 1 Mb. To complement the first-generation domestic cat maps, support higher ...resolution mapping studies, and aid genome assembly in specific areas as well as in the whole genome, a 15,000(Rad) radiation hybrid (RH) panel for the domestic cat was generated. Fibroblasts from the female Abyssinian cat that was used to generate the cat genomic sequence were fused to a Chinese hamster cell line (A23), producing 150 hybrid lines. The clones were initially characterized using 39 short tandem repeats (STRs) and 1,536 SNP markers. The utility of whole-genome amplification in preserving and extending RH panel DNA was also tested using 10 STR markers; no significant difference in retention was observed. The resolution of the 15,000(Rad) RH panel was established by constructing framework maps across 10 different 1-Mb regions on different feline chromosomes. In these regions, 2-point analysis was used to estimate RH distances, which compared favorably with the estimation of physical distances. The study demonstrates that the 15,000(Rad) RH panel constitutes a powerful tool for constructing high-resolution maps, having an average resolution of 40.1 kb per marker across the ten 1-Mb regions. In addition, the RH panel will complement existing genomic resources for the domestic cat, aid in the accurate re-assemblies of the forthcoming cat genomic sequence, and support cross-species genomic comparisons.
The progressive loss of colour in the hair of grey horses is controlled by a dominantly inherited allele at the Grey locus (GG). In this study, two paternal Quarter Horse (QH) families segregating ...for the GG allele were genotyped with a set of 101 microsatellite markers spanning the 31 autosomes and the X chromosome. This genome scan demonstrated linkage of Grey to COR018 (RF=0.02, LOD=12.04) on horse chromosome 25 (ECA25). Further chromosome‐specific analysis of seven total QH families confirmed the linkage of Grey to a group of ECA25 markers and the map order of NVHEQ43‐(0.24)‐UCDEQ405‐(0.09)‐COR080‐(0.05)‐GREY‐(0.14)‐UCDEQ464 was produced. Although G was found to be linked to TXN and COR018 in the chromosome‐specific analysis, the data were not sufficiently informative to place either marker on our ECA25 map with significant LODs. Our results excluded the equine tyrosinase related protein 1 (TYRP1) and melanocyte protein 17 (Pmel17) genes as possible candidates for the grey phenotype in horses.
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