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1.
Phys Rev Lett ; 126(14): 141301, 2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33891448

RESUMO

We present the first joint analysis of cluster abundances and auto or cross-correlations of three cosmic tracer fields: galaxy density, weak gravitational lensing shear, and cluster density split by optical richness. From a joint analysis (4×2pt+N) of cluster abundances, three cluster cross-correlations, and the auto correlations of the galaxy density measured from the first year data of the Dark Energy Survey, we obtain Ω_{m}=0.305_{-0.038}^{+0.055} and σ_{8}=0.783_{-0.054}^{+0.064}. This result is consistent with constraints from the DES-Y1 galaxy clustering and weak lensing two-point correlation functions for the flat νΛCDM model. Consequently, we combine cluster abundances and all two-point correlations from across all three cosmic tracer fields (6×2pt+N) and find improved constraints on cosmological parameters as well as on the cluster observable-mass scaling relation. This analysis is an important advance in both optical cluster cosmology and multiprobe analyses of upcoming wide imaging surveys.

2.
Phys Rev Lett ; 126(9): 091101, 2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33750144

RESUMO

We perform a comprehensive study of Milky Way (MW) satellite galaxies to constrain the fundamental properties of dark matter (DM). This analysis fully incorporates inhomogeneities in the spatial distribution and detectability of MW satellites and marginalizes over uncertainties in the mapping between galaxies and DM halos, the properties of the MW system, and the disruption of subhalos by the MW disk. Our results are consistent with the cold, collisionless DM paradigm and yield the strongest cosmological constraints to date on particle models of warm, interacting, and fuzzy dark matter. At 95% confidence, we report limits on (i) the mass of thermal relic warm DM, m_{WDM}>6.5 keV (free-streaming length, λ_{fs}≲10h^{-1} kpc), (ii) the velocity-independent DM-proton scattering cross section, σ_{0}<8.8×10^{-29} cm^{2} for a 100 MeV DM particle mass [DM-proton coupling, c_{p}≲(0.3 GeV)^{-2}], and (iii) the mass of fuzzy DM, m_{ϕ}>2.9×10^{-21} eV (de Broglie wavelength, λ_{dB}≲0.5 kpc). These constraints are complementary to other observational and laboratory constraints on DM properties.

3.
Mol Genet Genomics ; 268(4): 518-24, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12471449

RESUMO

The pst operon of Escherichia coli, which encodes the phosphate-specific transport system, is composed of five genes, pstS, pstC, pstA, pstB and phoU, whose transcription is induced by phosphate starvation. A phosphate-regulated promoter located upstream of the most proximal gene ( pstS) controls the transcription of the entire operon. Though the full-length pst mRNA could be detected by an improved RT-PCR protocol, Northern analysis using several pst-specific probes failed to reveal this transcript. Instead, smaller but distinct pst mRNA species were evident. Primer-extension experiments localized the 5' ends of pst mRNAs within the operon. The data suggest that the full-length mRNA is rapidly processed post-transcriptionally.


Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Proteínas de Bactérias/genética , Escherichia coli/genética , Óperon/genética , Transcrição Gênica , Fosfatase Alcalina/metabolismo , Northern Blotting , Primers do DNA/química , Família Multigênica/genética , Fosfatos/metabolismo , Regiões Promotoras Genéticas , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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