15 research outputs found
Cross-correlation between cosmic microwave background anisotropies and future galaxy surveys
The cosmic microwave background (CMB) is a snapshot of the Universe
at early times (z ∼ 1100). In the recent years, several experiments have
provided constraints on the concordance ΛCDM model from a statistical analysis of the CMB anisotropies. On the other hand, many galaxy
surveys will measure the 3D distribution of the dark matter component
of the Universe with unprecedented sensitivity and sky coverage. This is
a complementary probe to the CMB, since it traces the evolution of the
Universe at low redshift.
The addition of the two probes will break degeneracies in the parameters which are left when using either CMB or large scale structure (LSS).
Moreover, the contributions to the CMB anisotropies along the line-ofsight -the so-called secondary CMB anisotropies- are correlated with the
growth of perturbations at low redshift. Therefore, we have an important
information in addition to the simple combination of the CMB with large
scale structure (LSS) probes from galaxy surveys: the cross-correlation between the CMB and LSS probes, such as galaxy number counts and weak
lensing. In this thesis, we study the capability of the CMB-LSS crosscorrelation for constraining cosmological parameters alone or in combination with the CMB and LSS, using mock data and statistical methodologies, in the perspective of upcoming and future cosmological surveys.
First, we explore the capabilities of the lensing ratio between the CMB
lensing - galaxy clustering and weak lensing - galaxy clustering crosscorrelations, an estimator that under certain approximations is independent on some astrophysical uncertainties such as the galaxy bias and on the
multipoles. We forecast a measurement of this ratio with an error around
1-2% using Euclid and future CMB lensing experiments. Furthermore,
we evaluate the impact on this ratio of the inclusion of general relativity contributions to the galaxy number counts. We find that accounting for
the lensing magnification contribution induces a multipole dependence of
the ratio that will not be negligible for future surveys, and propose a new
estimator in order to take it into account. With the new formalism, we
forecast by a Fisher matrix approach the capability of the lensing ratio
for constraining cosmological parameters when it is added to the CMB
information. We find that in extended cosmological models the lensing
ratio can improve the errors on the dark energy parameters of state and
on the curvature density.
We have also investigated the global importance of the CMB - LSS
cross-correlation in a 2D tomographic approach for a joint analysis CMB
and galaxy number counts in the angular space. For this, we compute by
a Fisher matrix approach the joint constraints on many extended cosmological models, including the dark energy parametrization for a redshift
dependent equation of state, neutrino physics and primordial Universe parameters. We find that the inclusion of cross-correlation can improve the
dark energy figure of merit up to a factor ∼ 2. We forecast a detection
of the neutrino mass with ∼> 3σ significance by combining CMB-S4 with
SPHEREx, just by the analysis of quasi-linear scales. We also predict the
measurement of the primordial local non-Gaussianity parameter fNL with
an uncertaintiy ∼1-2 by combining the CMB with future radio continuum
surveys such as SKA. Our methodology is then applied to models of features caused by deviations from a power law primordial power spectrum.
We find that the cross-correlation is useful for helping to constrain these
models, in particular for surveys with large redshift coverage such as the
radio continuum ones. As a further step, we extend the analysis to the
inclusion of weak lensing as additional probe and present the results for
the combination of the full Euclid likelihood with the CMB.El Fondo C´osmico de Microondas (FCM) es una imagen del universo temprano (z ∼ 1100). En los ´ultimos a˜nos, varios experimentos han conseguido restringir los par´ametros del modelo concordante ΛCDM a partir
de un an´alisis estad´ıstico de las anisotrop´ıas del FCM. Por otra parte,
varios cartografiados de galaxias medir´an la distribuci´on tridimensional
de la componente de materia oscura del Universo con una sensibilidad y
cobertura sin precedentes. Esta es una herramienta complementaria al
FCM, ya que traza la evoluci´on del universo a bajo redshift.
La combinaci´on de las dos pruebas romper´a degeneraciones entre
par´ametros que permanecen cuando se utilizan o bien el FCM o la estructura a gran escala de manera aislada. Adem´as, las contribuciones a
las anisotrop´ıas del FCM a lo largo de la l´ınea de visi´on -las llamadas
anisotrop´ıas secundarias- est´an correlacionadas con el crecimiento de las
perturbaciones a bajo redshift. Por tanto, disponemos de informaci´on
relevante adem´as de la simple combinaci´on del FCM y las pruebas de estructura a gran escala proporcionadas por los cartografiados de galaxias:
la correlaci´on cruzada entre el FCM y los trazadores de la estructura a
gran escala, como el n´umero de cuentas de galaxias o el efecto lente d´ebil.
En esta tesis, estudiamos la capacidad de la correlaci´on cruzada entre
FCM y estructura a gran escala para restringir par´ametros cosmol´ogicos,
por s´ı sola o en combinaci´on con el FCM y la estructura a gran escala,
mediante datos simulados y herramientas estad´ısticas, y en la perspectiva
de futuros cartografiados cosmol´ogicos.
En primer lugar, exploramos las capacidades del cociente de efecto
lente entre las correlaciones cruzadas del efecto lente del FCM con el
n´umero de cuentas galaxias, y del efecto lente de galaxias con el n´umero
de cuentas de galaxias; un estimador que bajo ciertas aproximaciones es independiente de ciertas incertidumbres astrof´ısicas como el bias de las
galaxias y de los multipolos. Predecimos una medici´on de este cociente
con un error en torno al 1-2%, usando Euclid y futuros experimentos de
FCM para el efecto lente. Adem´as, evaluamos el impacto en el cociente
de la inclusi´on de las contribuciones de relatividad general en el n´umero
de cuentas de galaxias. Hallamos que la magnificaci´on por efecto lente
provoca una dependencia de los multipolos que no es despreciable para
futuros cartografiados de galaxias, y proponemos un nuevo estimador para
tener este efecto en cuenta. En el nuevo formalismo, predecimos mediante
una aproximaci´on de matriz Fisher la capacidad del cociente de efecto
lente para restringir par´ametros cosmol´ogicos cuando es combinado con la
informaci´on del FCM. Encontramos que, para modelos extendidos, a˜nadir
el cociente puede mejorar los errores en los par´ametros de estado de la
energ´ıa oscura y en la densidad de curvatura.
Despu´es, estudiamos la importancia global de la correlaci´on cruzada
entre el FCM y la estructura a gran escala mediante una aproximaci´on
2D tomogr´afica en el espacio angular para el an´alisis conjunto del FCM
y el n´umero de cuentas de galaxias. Para ello, calculamos mediante una
aproximaci´on de matriz Fisher conjunta los errores en par´ametros de varios modelos cosmol´ogicos extendidos, incluyendo la parametrizaci´on de
una ecuaci´on de estado de la energ´ıa oscura que depende del redshift,
f´ısica de neutrinos y par´ametros relacionados con el Universo primordial.
Encontramos que la inclusi´on de la correlaci´on cruzada puede mejorar
la figura de m´erito de la energ´ıa oscura hasta un factor ∼ 2. Predecimos una detecci´on de la masa del neutrino con un grado de significaci´on
superior a 3σ mediante la combinaci´on de los experimentos CMB-S4 y
SPHEREx, s´olo con el an´alisis de escalas cuasi-lineales. Tambi´en predecimos la medida del par´ametro local de no Gaussianidad primordial fNL
con una incertidumbre en torno a ∼ 1 − 2 mediante la combinaci´on del
FCM con futuros cartografiados en el radio continuo como SKA. Nuestra
metodolog´ıa es tambi´en aplicada a modelos de posibles rasgos causados
por desviaciones de una ley de potencias para el espectro de potencias
primordial. Encontramos que la correlaci´on cruzada es ´util para ayudar a restringir estos modelos, en particular para cartografiados con gran
cobertura en redshift como los de radio continuo. Como siguiente paso,
extendemos este an´alisis conjunto bidimensional a la inclusi´on del efecto
lente d´ebil de galaxias como prueba adicional y presentamos los resultados
para la combinaci´on de la likelihood completa de Euclid con el FCM
Cosmological parameter forecasts by a joint 2D tomographic approach to CMB and galaxy clustering
Measuring lensing ratios with future cosmological surveys
The ratio between the CMB lensing/galaxy counts and the galaxy shear/galaxy counts cross-correlations combines the information from different cosmological probes to infer cosmographic measurements that are less dependent on astrophysical uncertainties and can constrain the geometry of the Universe. We discuss the future perspectives for the measurement of this lensing ratio as previously introduced, i.e., with the use of the Limber and flat-sky approximations and neglecting all the effects on the galaxy survey from observing on the past light cone. We then show how the cosmological information in this estimator is affected by the Limber approximation and by the inclusion of the redshift space distortions (RSD) and lensing magnification contributions to the galaxy number counts
Early Science with the Large Millimeter Telescope: Detection of Dust Emission in Multiple Images of a Normal Galaxy at z \u3e 4 Lensed by a Frontier Fields Cluster
We directly detect dust emission in an optically detected, multiply imaged galaxy lensed by the Frontier Fields cluster MACSJ0717.5+3745. We detect two images of the same galaxy at 1.1 mm with the AzTEC camera on the Large Millimeter Telescope leaving no ambiguity in the counterpart identification. This galaxy, MACS0717_Az9, is at z \u3e 4 and the strong lensing model (μ=7.5) allows us to calculate an intrinsic IR luminosity of 9.7 × 1010 Le and an obscured star formation rate of 14.6 ± 4.5 Me yr−1. The unobscured star formation rate from the UV is only 4.1 ± 0.3 Me yr−1, which means the total star formation rate (18.7 ± 4.5 Me yr−1) is dominated (75%–80%) by the obscured component. With an intrinsic stellar mass of only 6.9 × 109 Me, MACS0717_Az9 is one of only a handful of z \u3e 4 galaxies at these lower masses that is detected in dust emission. This galaxy lies close to the estimated star formation sequence at this epoch. However, it does not lie on the dust obscuration relation (IRX-β) for local starburst galaxies and is instead consistent with the Small Magellanic Cloud attenuation law. This remarkable lower mass galaxy, showing signs of both low metallicity and high dust content, may challenge our picture of dust production in the early universe
Role of age and comorbidities in mortality of patients with infective endocarditis
[Purpose]: The aim of this study was to analyse the characteristics of patients with IE in three groups of age and to assess the ability of age and the Charlson Comorbidity Index (CCI) to predict mortality.
[Methods]: Prospective cohort study of all patients with IE included in the GAMES Spanish database between 2008 and 2015.Patients were stratified into three age groups:<65 years,65 to 80 years,and ≥ 80 years.The area under the receiver-operating characteristic (AUROC) curve was calculated to quantify the diagnostic accuracy of the CCI to predict mortality risk.
[Results]: A total of 3120 patients with IE (1327 < 65 years;1291 65-80 years;502 ≥ 80 years) were enrolled.Fever and heart failure were the most common presentations of IE, with no differences among age groups.Patients ≥80 years who underwent surgery were significantly lower compared with other age groups (14.3%,65 years; 20.5%,65-79 years; 31.3%,≥80 years). In-hospital mortality was lower in the <65-year group (20.3%,<65 years;30.1%,65-79 years;34.7%,≥80 years;p < 0.001) as well as 1-year mortality (3.2%, <65 years; 5.5%, 65-80 years;7.6%,≥80 years; p = 0.003).Independent predictors of mortality were age ≥ 80 years (hazard ratio [HR]:2.78;95% confidence interval [CI]:2.32–3.34), CCI ≥ 3 (HR:1.62; 95% CI:1.39–1.88),and non-performed surgery (HR:1.64;95% CI:11.16–1.58).When the three age groups were compared,the AUROC curve for CCI was significantly larger for patients aged <65 years(p < 0.001) for both in-hospital and 1-year mortality.
[Conclusion]: There were no differences in the clinical presentation of IE between the groups. Age ≥ 80 years, high comorbidity (measured by CCI),and non-performance of surgery were independent predictors of mortality in patients with IE.CCI could help to identify those patients with IE and surgical indication who present a lower risk of in-hospital and 1-year mortality after surgery, especially in the <65-year group
Natural History of MYH7-Related Dilated Cardiomyopathy
BACKGROUND Variants in myosin heavy chain 7 (MYH7) are responsible for disease in 1% to 5% of patients with dilated cardiomyopathy (DCM); however, the clinical characteristics and natural history of MYH7-related DCM are poorly described. OBJECTIVES We sought to determine the phenotype and prognosis of MYH7-related DCM. We also evaluated the influence of variant location on phenotypic expression. METHODS We studied clinical data from 147 individuals with DCM-causing MYH7 variants (47.6% female; 35.6 +/- 19.2 years) recruited from 29 international centers. RESULTS At initial evaluation, 106 (72.1%) patients had DCM (left ventricular ejection fraction: 34.5% +/- 11.7%). Median follow-up was 4.5 years (IQR: 1.7-8.0 years), and 23.7% of carriers who were initially phenotype-negative developed DCM. Phenotypic expression by 40 and 60 years was 46% and 88%, respectively, with 18 patients (16%) first diagnosed at <18 years of age. Thirty-six percent of patients with DCM met imaging criteria for LV noncompaction. During follow-up, 28% showed left ventricular reverse remodeling. Incidence of adverse cardiac events among patients with DCM at 5 years was 11.6%, with 5 (4.6%) deaths caused by end-stage heart failure (ESHF) and 5 patients (4.6%) requiring heart transplantation. The major ventricular arrhythmia rate was low (1.0% and 2.1% at 5 years in patients with DCM and in those with LVEF of <= 35%, respectively). ESHF and major ventricular arrhythmia were significantly lower compared with LMNA-related DCM and similar to DCM caused by TTN truncating variants. CONCLUSIONS MYH7-related DCM is characterized by early age of onset, high phenotypic expression, low left ventricular reverse remodeling, and frequent progression to ESHF. Heart failure complications predominate over ventricular arrhythmias, which are rare. (C) 2022 The Authors. Published by Elsevier on behalf of the American College of Cardiology Foundation
Microwave spectro-polarimetry of matter and radiation across space and time
From Springer Nature via Jisc Publications RouterHistory: received 2020-07-29, accepted 2021-03-02, registration 2021-03-03, pub-print 2021-06, pub-electronic 2021-07-03, online 2021-07-03Publication status: PublishedAbstract: This paper discusses the science case for a sensitive spectro-polarimetric survey of the microwave sky. Such a survey would provide a tomographic and dynamic census of the three-dimensional distribution of hot gas, velocity flows, early metals, dust, and mass distribution in the entire Hubble volume, exploit CMB temperature and polarisation anisotropies down to fundamental limits, and track energy injection and absorption into the radiation background across cosmic times by measuring spectral distortions of the CMB blackbody emission. In addition to its exceptional capability for cosmology and fundamental physics, such a survey would provide an unprecedented view of microwave emissions at sub-arcminute to few-arcminute angular resolution in hundreds of frequency channels, a data set that would be of immense legacy value for many branches of astrophysics. We propose that this survey be carried out with a large space mission featuring a broad-band polarised imager and a moderate resolution spectro-imager at the focus of a 3.5 m aperture telescope actively cooled to about 8K, complemented with absolutely-calibrated Fourier Transform Spectrometer modules observing at degree-scale angular resolution in the 10–2000 GHz frequency range. We propose two observing modes: a survey mode to map the entire sky as well as a few selected wide fields, and an observatory mode for deeper observations of regions of specific interest
Early Science with the Large Millimeter Telescope: Detection of Dust Emission in Multiple Images of a Normal Galaxy at z > 4 Lensed by a Frontier Fields Cluster
We directly detect dust emission in an optically detected, multiply imaged galaxy lensed by the Frontier Fields cluster MACSJ0717.5+3745. We detect two images of the same galaxy at 1.1 mm with the AzTEC camera on the Large Millimeter Telescope leaving no ambiguity in the counterpart identification. This galaxy, MACS0717_Az9, is at z > 4 and the strong lensing model (mu = 7.5) allows us to calculate an intrinsic IR luminosity of 9.7 x 10(10) L-circle dot and an obscured star formation rate of 14.6 +/- 4.5 M-circle dot yr(-1). The unobscured star formation rate from the UV is only 4.1 +/- 0.3 M-circle dot yr(-1), which means the total star formation rate (18.7 +/- 4.5 M-circle dot yr(-1)) is dominated (75%-80%) by the obscured component. With an intrinsic stellar mass of only 6.9 x 10(9) M circle dot, MACS0717_Az9 is one of only a handful of z. >. 4 galaxies at these lower masses that is detected in dust emission. This galaxy lies close to the estimated star formation sequence at this epoch. However, it does not lie on the dust obscuration relation (IRX-beta) for local starburst galaxies and is instead consistent with the Small Magellanic Cloud attenuation law. This remarkable lower mass galaxy, showing signs of both low metallicity and high dust content, may challenge our picture of dust production in the early universe.US National Science Foundation (NSF) via the University Radio Observatory program; University of Massachusetts, Amherst; HST Frontier Fields program; NASA [NAS5-26555]; CONACYT [CB-2011-01-1672, CB-2011-01-167281]; CNRS; CNES; NSF [1513473]; NASA through a grant from STScI [HST-AR-14302]; NASA through Hubble Fellowship - Space Telescope Science Institute [HF2-51368]; Mexican Science and Technology Funding Agency, CONACYTThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]
Prosthetic Valve Candida spp. Endocarditis: New Insights Into Long-term Prognosis—The ESCAPE Study
International audienceBackground: Prosthetic valve endocarditis caused by Candida spp. (PVE-C) is rare and devastating, with international guidelines based on expert recommendations supporting the combination of surgery and subsequent azole treatment.Methods: We retrospectively analyzed PVE-C cases collected in Spain and France between 2001 and 2015, with a focus on management and outcome.Results: Forty-six cases were followed up for a median of 9 months. Twenty-two patients (48%) had a history of endocarditis, 30 cases (65%) were nosocomial or healthcare related, and 9 (20%) patients were intravenous drug users. "Induction" therapy consisted mainly of liposomal amphotericin B (L-amB)-based (n = 21) or echinocandin-based therapy (n = 13). Overall, 19 patients (41%) were operated on. Patients <66 years old and without cardiac failure were more likely to undergo cardiac surgery (adjusted odds ratios [aORs], 6.80 [95% confidence interval [CI], 1.59-29.13] and 10.92 [1.15-104.06], respectively). Surgery was not associated with better survival rates at 6 months. Patients who received L-amB alone had a better 6-month survival rate than those who received an echinocandin alone (aOR, 13.52; 95% CI, 1.03-838.10). "Maintenance" fluconazole therapy, prescribed in 21 patients for a median duration of 13 months (range, 2-84 months), led to minor adverse effects.Conclusion: L-amB induction treatment improves survival in patients with PVE-C. Medical treatment followed by long-term maintenance fluconazole may be the best treatment option for frail patients
Role of age and comorbidities in mortality of patients with infective endocarditis.
The aim of this study was to analyse the characteristics of patients with IE in three groups of age and to assess the ability of age and the Charlson Comorbidity Index (CCI) to predict mortality. Prospective cohort study of all patients with IE included in the GAMES Spanish database between 2008 and 2015.Patients were stratified into three age groups: A total of 3120 patients with IE (1327 There were no differences in the clinical presentation of IE between the groups. Age ≥ 80 years, high comorbidity (measured by CCI),and non-performance of surgery were independent predictors of mortality in patients with IE.CCI could help to identify those patients with IE and surgical indication who present a lower risk of in-hospital and 1-year mortality after surgery, especially in th