Designing an Optimal Kilonova Search Using DECam for Gravitational-wave Events

Artículo escrito por un elevado número de autores, solo se referencian el que aparece en primer lugar, el nombre del grupo de colaboración, si le hubiere, y los autores pertenecientes a la UAMWe address the problem of optimally identifying all kilonovae detected via gravitational-wave emission in the upcoming LIGO/Virgo/KAGRA observing run, O4, which is expected to be sensitive to a factor of ∼7 more binary neutron star (BNS) alerts than previously. Electromagnetic follow-up of all but the brightest of these new events will require >1 m telescopes, for which limited time is available. We present an optimized observing strategy for the DECam during O4. We base our study on simulations of gravitational-wave events expected for O4 and wide-prior kilonova simulations. We derive the detectabilities of events for realistic observing conditions. We optimize our strategy for confirming a kilonova while minimizing telescope time. For a wide range of kilonova parameters, corresponding to a fainter kilonova compared to GW170817/AT 2017gfo, we find that, with this optimal strategy, the discovery probability for electromagnetic counterparts with the DECam is ∼80% at the nominal BNS gravitational-wave detection limit for O4 (190 Mpc), which corresponds to an ∼30% improvement compared to the strategy adopted during the previous observing run. For more distant events (∼330 Mpc), we reach an ∼60% probability of detection, a factor of ∼2 increase. For a brighter kilonova model dominated by the blue component that reproduces the observations of GW170817/AT 2017gfo, we find that we can reach ∼90% probability of detection out to 330 Mpc, representing an increase of ∼20%, while also reducing the total telescope time required to follow up events by ∼20%The DES participants from Spanish institutions are partially supported by MICINN under grants ESP2017-89838, PGC2018-094773, PGC2018-102021, SEV2016-0588, SEV-2016-0597, and MDM-2015-050

The Dark Energy Survey Supernova Program results: Type Ia Supernova brightness correlates with host galaxy dust

This is an electronic version of an article published in Monthly Notices of the Royal Astronomical Society. C. Meldorf et al. in “The Dark Energy Survey Supernova Program results: Type Ia Supernova brightness correlates with host galaxy dust”. Monthly Notices of the Royal Astronomical Society 518.2 (2023): 1985-2004Artículo escrito por un elevado número de autores, solo se referencian el que aparece en primer lugar, los autores pertenecientes a la UAM y el nombre del grupo de colaboración, si lo hubiereCosmological analyses with type Ia supernovae (SNe Ia) often assume a single empirical relation between color and luminosity (β) and do not account for varying host-galaxy dust properties. However, from studies of dust in large samples of galaxies, it is known that dust attenuation can vary significantly. Here we take advantage of state-of-the-art modeling of galaxy properties to characterize dust parameters (dust attenuation AV , and a parameter describing the dust law slope RV ) for the Dark Energy Survey (DES) SN Ia host galaxies using the publicly available BAGPIPES code. Utilizing optical and infrared data of the hosts alone, we find three key aspects of host dust that impact SN Ia cosmology: 1) there exists a large range (∼ 1 − 6) of host RV 2) high stellar mass hosts have RV on average ∼ 0.7 lower than that of low-mass hosts 3) there is a significant (> 3σ) correlation between the Hubble diagram residuals of red SNe Ia that when corrected for reduces scatter by ∼ 13% and the significance of the “mass step” to ∼ 1σ. These represent independent confirmations of recent predictions based on dust that attempted to explain the puzzling “mass step” and intrinsic scatter (σint) in SN Ia analyses. We also find that red-sequence galaxies have both lower and more peaked dust law slope distributions on average in comparison to non red-sequence galaxies. We find that the SN Ia β and σint both differ by > 3σ when determined separately for red-sequence galaxy and all other galaxy hosts. The agreement between fitted host-RV and SN Ia β & σint suggests that host dust properties play a major role in SN Ia color-luminosity standardization and supports the claim that SN Ia intrinsic scatter is driven by RV variatio

Effectiveness of a Surgery Admission Unit for patients undergoing major elective surgery in a tertiary university hospital

<p>Abstract</p> <p>Background</p> <p>The increasing demand on hospitalisation, either due to elective activity from the waiting lists or due to emergency admissions coming from the Emergency Department (ED), requires looking for strategies that lead to effective bed management. The aim of this study was to evaluate the effectiveness of a surgery admission unit for major elective surgery patients who were admitted for same-day surgery.</p> <p>Methods</p> <p>We included all patients admitted for elective surgery in a university tertiary hospital between the 1st of September and the 31st of December 2006, as well as those admitted during the same period of 2008, after the introduction of the Surgery Admission Unit. The main outcome parameters were global length of stay, pre-surgery length of stay, proportion of patients admitted the same day of the surgery and number of cancellations. Differences between the two periods were evaluated by the T-test and Chi-square test. Significance at P < 0.05 was assumed throughout.</p> <p>Results</p> <p>We included 6,053 patients, 3,003 during 2006 and 3,050 patients during 2008. Global length of stay was 6.2 days (IC 95%:6.4-6) in 2006 and 5.5 days (IC 95%:5.8-5.2) in 2008 (p < 0.005). Pre-surgery length of stay was reduced from 0.46 days (IC 95%:0.44-0.48) in 2006 to 0.29 days (IC 95%:0.27-0.31) in 2008 (p < 0.005). The proportion of patients admitted for same-day surgery was 67% (IC 95%:69%-65%) in 2006 and 76% (IC 95%:78%-74%) in 2008 (p < 0.005). The number of cancelled interventions due to insufficient preparation was 31 patients in 2006 and 7 patients in 2008.</p> <p>Conclusions</p> <p>The implementation of a Surgery Admission Unit for patients undergoing major elective surgery has proved to be an effective strategy for improving bed management. It has enabled an improvement in the proportion of patients admitted on the same day as surgery and a shorter length of stay.</p

Dark Energy Survey Year 3 results: Cosmological constraints from galaxy clustering and weak lensing

Artículo escrito por un elevado número de autores, solo se referencian el que aparece en primer lugar, el nombre del grupo de colaboración, si le hubiere, y los autores pertenecientes a la UAMWe present the first cosmology results from large-scale structure using the full 5000 deg2 of imaging data from the Dark Energy Survey (DES) Data Release 1. We perform an analysis of large-scale structure combining three two-point correlation functions (3 × 2pt): (i) cosmic shear using 100 million source galaxies, (ii) galaxy clustering, and (iii) the cross-correlation of source galaxy shear with lens galaxy positions, galaxy-galaxy lensing. To achieve the cosmological precision enabled by these measurements has required updates to nearly every part of the analysis from DES Year 1, including the use of two independent galaxy clustering samples, modeling advances, and several novel improvements in the calibration of gravitational shear and photometric redshift inference. The analysis was performed under strict conditions to mitigate confirmation or observer bias; we describe specific changes made to the lens galaxy sample following unblinding of the results and tests of the robustness of our results to this decision. We model the data within the flat ΛCDM and wCDM cosmological models, marginalizing over 25 nuisance parameters. We find consistent cosmological results between the three two-point correlation functions; their combination yields clustering amplitude S8 = 0.776-0.017+0.017 and matter density ωm = 0.339-0.031+0.032 in ΛCDM, mean with 68% confidence limits; S8 = 0.775-0.024+0.026, ωm = 0.352-0.041+0.035, and dark energy equation-of-state parameter w = -0.98-0.20+0.32 in wCDM. These constraints correspond to an improvement in signal-to-noise of the DES Year 3 3 × 2pt data relative to DES Year 1 by a factor of 2.1, about 20% more than expected from the increase in observing area alone. This combination of DES data is consistent with the prediction of the model favored by the Planck 2018 cosmic microwave background (CMB) primary anisotropy data, which is quantified with a probability-to-exceed p=0.13-0.48. We find better agreement between DES 3 × 2pt and Planck than in DES Y1, despite the significantly improved precision of both. When combining DES 3 × 2pt data with available baryon acoustic oscillation, redshift-space distortion, and type Ia supernovae data, we find p = 0.34. Combining all of these datasets with Planck CMB lensing yields joint parameter constraints of S8 = 0.812-0.008+0.008, ωm = 0.306-0.005+0.004, h = 0.680-0.003+0.004, and mν<0.13 eV (95% C.L.) in ΛCDM; S8 = 0.812-0.008+0.008, ωm=0.302-0.006+0.006, h = 0.687-0.007+0.006, and w = -1.031-0.027+0.030 in wCD

Longevity, body dimension and reproductive mode drive differences in aquatic versus terrestrial life-history strategies

1. Aquatic and terrestrial environments display stark differences in key environmental factors and phylogenetic composition but their consequences for the evolution of species' life-history strategies remain poorly understood. 2. Here, we examine whether and how life-history strategies vary between terrestrial and aquatic species. We use demographic information for 685 terrestrial and 122 aquatic animal and plant species to estimate key life-history traits. We then use phylogenetically corrected least squares regression to explore potential differences in trade-offs between life-history traits between both environments. We contrast life-history strategies of aquatic versus terrestrial species in a principal component analysis while accounting for body dimensions and phylogenetic relationships. 3. Our results show that the same trade-offs structure terrestrial and aquatic life histories, resulting in two dominant axes of variation that describe species' pace of life and reproductive strategies. Terrestrial plants display a large diversity of strategies, including the longest-lived species in this study. Aquatic animals exhibit higher reproductive frequency than terrestrial animals. When correcting for body size, mobile and sessile terrestrial organisms show slower paces of life than aquatic ones. 4. Aquatic and terrestrial species are ruled by the same life-history trade-offs, but have evolved different strategies, likely due to distinct environmental selective pressures. Such contrasting life-history strategies have important consequences for the conservation and management of aquatic and terrestrial species

Population pharmacokinetics of the two enantiomers of tramadol and O -demethyl tramadol after surgery in children

International audienceBACKGROUND : Few data are available on the stereoselective pharmacokinetics of tramadol in children. The aim of this study was to develop a population pharmacokinetic model for the (+)- and (-)-enantiomers of tramadol and its O-demethyl tramadol metabolite (M1) in children.METHODS : Twenty-five children (1-8 yr) were included in this study. Tramadol was administered after surgery by continuous infusion (loading dose, 2 mg kg(-1) i.v. over 10 min followed by continuous infusion of 8 mg kg(-1) over 24 h). If pain relief was inadequate, additional 1 mg kg(-1) i.v. bolus doses of tramadol were given over 10 min. A two-compartment structural model was used with NONMEM.RESULTS : For both enantiomers of tramadol, weight was the only patient characteristic parameter showing significant covariate effects on clearance (CL). CL increased by 5.7-6.1 litre h(-1) between 8-12 and 13-16 kg, and by 2.4-3.3 litre h(-1) between 13-16 and 17-33 kg. The rate constants associated with the metabolite elimination [0.144 h(-1), (+)-M1 and 0.18 h(-1), (-)-M1] were smaller than the elimination rate constants of the parent drugs [0.243 h(-1), (+)-tramadol and 0.241 h(-1), (-)-tramadol], suggesting that the metabolite disposition was rate-limited by its elimination. The presence of two subpopulations of patients was suspected on the basis of the observed bimodal distributions of the AUC(M1)/AUC(tramadol) ratios.CONCLUSIONS : The results of this study combine relationships between tramadol CL and patient covariates that may be useful for dose adjustment. Polymorphism is likely to contribute to the interpatient variability observed in the AUC M1/AUC tramadol ratios

The first Hubble diagram and cosmological constraints using superluminous supernovae

Artículo escrito por un elevado número de autores, solo se referencian el que aparece en primer lugar, el nombre del grupo de colaboración, si le hubiere, y los autores pertenecientes a la UA

Consistency of cosmic shear analyses in harmonic and real space

Artículo escrito por un elevado número de autores, solo se referencian el que aparece en primer lugar, el nombre del grupo de colaboración, si le hubiere, y los autores pertenecientes a la UA