Error analysis in cross-correlation of sky maps: application to the ISW detection

Constraining cosmological parameters from measurements of the Integrated Sachs-Wolfe effect requires developing robust and accurate methods for computing statistical errors in the cross-correlation between maps. This paper presents a detailed comparison of such error estimation applied to the case of cross-correlation of Cosmic Microwave Background (CMB) and large-scale structure data. We compare theoretical models for error estimation with montecarlo simulations where both the galaxy and the CMB maps vary around a fiducial auto-correlation and cross-correlation model which agrees well with the current concordance LCDM cosmology. Our analysis compares estimators both in harmonic and configuration (or real) space, quantifies the accuracy of the error analysis and discuss the impact of partial sky survey area and the choice of input fiducial model on dark-energy constraints. We show that purely analytic approaches yield accurate errors even in surveys that cover only 10% of the sky and that parameter constraints strongly depend on the fiducial model employed. Alternatively, we discuss the advantages and limitations of error estimators that can be directly applied to data. In particular, we show that errors and covariances from the Jack-Knife method agree well with the theoretical approaches and simulations. We also introduce a novel method in real space that is computationally efficient and can be applied to real data and realistic survey geometries. Finally, we present a number of new findings and prescriptions that can be useful for analysis of real data and forecasts, and present a critical summary of the analyses done to date.Comment: submitted to MNRAS, 26 page

Evaluation of Hormonal Contraception Effects on Strength and Recovery Across the Hormone Cycle

Few investigations have evaluated the effects of hormonal contraception on exercise performance. The biphasic response of endogenous hormones in eumenorrheic (EUM) females is altered with the delivery of exogenous hormones, with oral contraceptives (OC) and intrauterine devices (IUD) most commonly used. Hormonal alterations may have undesirable consequences on muscle strength and power performance, fatigability, and recovery. The purpose of the study was to evaluate the effects of OC and IUD use, compared to a EUM cycle, on maximal strength, power, fatigability, and recovery between menstrual cycle (MC) phases. Sixty healthy, active women who were monophasic OC users (n=21), had a hormonal-IUD (H-IUD; n=20), or had regular naturally occurring menstrual cycles or were using a non-hormonal IUD (EUM; n=19) were evaluated in the in the follicular phase/placebo pill (FP) or in the luteal phase/active pill (LP). Strength was assessed from upper and lower body one repetition max (1RM) and peak force from isometric dynamometry. Power was assessed from counter movement jump and reactive strength index. Peak power (PP), average power (AP), time to PP, and fatigue index were measured with a repeated sprint ability test (RSA). Blood lactate, vessel diameter, and blood flow were measured prior to and immediately post-RSA. Leg press 1RM was significantly different across the MC between groups (p=0.027), with higher leg press 1RM in the LP for the OC group (mean difference[MD: ∆LP-FP]±standard error [SE]: ∆7.3±4.5 kg; p=0.045) compared to the IUD group (∆-8.8±4.6 kg; p=0.045). The results showed no significant changes across the MC for other study outcomes (p>0.05). Despite no significance, the H-IUD group (Δ320.3±260.3 W) and EUM group (Δ24.0±13.3 W) demonstrated greater changes in AP and PP, respectively, in the LP while the OC exhibited greater AP in the FP (Δ-248.2±254.0 W). All groups demonstrated greater blood flow in the FP (OC:Δ-133.4±10.3 mL/min; H-IUD:Δ-128.6±10.6 mL/min; EUM:Δ-137.3±10.8 mL/min) after exercise. Collectively, OC and H-IUD users have similar performance and recovery across the MC, suggesting that exercise training does not need to be modified for phase or group. It appears that OC and H-IUD users can be equally included in research with EUM women.Doctor of Philosoph

Cross-correlation of WMAP 3rd year and the SDSS DR4 galaxy survey: new evidence for Dark Energy

We cross-correlate the third-year WMAP data with galaxy samples extracted from the SDSS DR4 (SDSS4) covering 13% of the sky, increasing by a factor of 3.7 the volume sampled in previous analyses. The new measurements confirm a positive cross-correlation with higher significance (total signal-to-noise of about 4.7). The correlation as a function of angular scale is well fitted by the integrated Sachs-Wolfe (ISW) effect for LCDM flat FRW models with a cosmological constant. The combined analysis of different samples gives Omega_L=0.80-0.85$(68$0.77-0.86$ (95% CL). We find similar best fit values for Omega_L for different galaxy samples with median redshifts of z ~0.3 and z ~0.5, indicating that the data scale with redshift as predicted by the LCDM cosmology (with equation of state parameter w=-1). This agreement is not trivial, but can not yet be used to break the degeneracy constraints in the w versus Omega_L plane using only the ISW data.Comment: 5 pages, final version to be published by MNRAS Let. Minor changes with some additional clarification on error analysis don

The prescence of Pseudocolopteryx citreola in eastern Argentina, with comparisons of voice with other doraditos

The Ticking Doradito (Pseudocolopteryx citreola) was included in P. flaviventris until a recent taxonomic revalidation. The plumages of the two species are virtually indistinguishable and so recording their vocalizations is necessary in order to identify the species with any certainty. In Chile P. citreola is found in the centre of the country and it is a migrant but its winter distribution is unknown. In Argentina the situation is more complicated as it is possible to find this species and P. flaviventris in the same areas. In Argentina P. citreola occurs in the foothills of the Andes from Río Negro to Salta and it even reaches low lying areas in Bolivia. We present the first two recordings of P. citreola vocalizations for the eastern sector of the Southern Cone (one from eastern Entre Ríos and the other from southwestern Buenos Aires province, Argentina, both in November). We comment on potential confusions created by our new data in reference to the distribution of P. flaviventris in the Cisandean region. Possibly our new records of P. citreola records represent a west-east migration pattern. A phonetical comparation and sonograms showing the differences between the song of this species and the other Pseudocolopteryx is presented. The voices of P. citreola resemble those of P. dinellianus and (to a lesser extent) those of P. acutipennis, and are markedly different from those of P. flaviventris. The voices of P. citreola in Salta province, northwestern Argentina, are somewhat different from those elsewhere, and merit further research.Fil: López Lanús, Bernabé. Audiornis Producciones; ArgentinaFil: Unterkofler, Darío E.. Aves Argentinas; ArgentinaFil: Ornstein, Ulises. Aves Argentinas; ArgentinaFil: Güller, Roberto. Aves Argentinas; ArgentinaFil: Lejarraga, Reginaldo. No especifica;Fil: Doiny Cabre, Cristobal. No especifica;Fil: Scoffield, Rosemary L.. Refugio de Vida Silvestre Marahué; ArgentinaFil: Kopuchian, Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; Argentin

Tracing The Sound Horizon Scale With Photometric Redshift Surveys

We propose a new method for cosmological parameters extraction using the baryon acoustic oscillation scale as a standard ruler in deep galaxy surveys with photometric determination of redshifts. The method consists in a simple empirical parametric fit to the angular 2-point correlation function w(theta). It is parametrized as a power law to describe the continuum plus a Gaussian to describe the BAO bump. The location of the Gaussian is used as the basis for the measurement of the sound horizon scale. This method, although simple, actually provides a robust estimation, since the inclusion of the power law and the use of the Gaussian removes the shifts which affect the local maximum. We discuss the effects of projection bias, non-linearities, redshift space distortions and photo-z precision, and apply our method to a mock catalog of the Dark Energy Survey, built upon a large N-body simulation provided by the MICE collaboration. We discuss the main systematic errors associated to our method and show that they are dominated by the photo-z uncertainty.Comment: 12 pages, 12 figures, published online in MNRAS, 25 October 201

Meropenem vs standard of care for treatment of neonatal late onset sepsis (NeoMero1): A randomised controlled trial.

BACKGROUND: The early use of broad-spectrum antibiotics remains the cornerstone for the treatment of neonatal late onset sepsis (LOS). However, which antibiotics should be used is still debatable, as relevant studies were conducted more than 20 years ago, recruited in single centres or countries, evaluated antibiotics not in clinical use anymore and had variable inclusion/exclusion criteria and outcome measures. Moreover, antibiotic-resistant bacteria have become a major problem in many countries worldwide. We hypothesized that efficacy of meropenem as a broad-spectrum antibiotic is superior to standard of care regimens (SOC) in empiric treatment of LOS and aimed to compare meropenem to SOC in infants aged 44 weeks meeting the Goldstein criteria of sepsis, were randomized in a 1:1 ratio to receive meropenem or one of the two SOC regimens (ampicillin+gentamicin or cefotaxime+gentamicin) chosen by each site prior to the start of the study for 8-14 days. The primary outcome was treatment success (survival, no modification of allocated therapy, resolution/improvement of clinical and laboratory markers, no need of additional antibiotics and presumed/confirmed eradication of pathogens) at test-of-cure visit (TOC) in full analysis set. Stool samples were tested at baseline and Day 28 for meropenem-resistant Gram-negative organisms (CRGNO). The primary analysis was performed in all randomised patients and in patients with culture confirmed LOS. Proportions of participants with successful outcome were compared by using a logistic regression model adjusted for the stratification factors. From September 3, 2012 to November 30th 2014, total of 136 patients (instead of planned 275) in each arm were randomized; 140 (52%) were culture positive. Successful outcome at TOC was achieved in 44/136 (32%) in the meropenem arm vs. 31/135 (23%) in the SOC arm (p = 0.087). The respective numbers in patients with positive cultures were 17/63 (27%) vs. 10/77 (13%) (p = 0.022). The main reason of failure was modification of allocated therapy. Treatment emergent adverse events occurred in 72% and serious adverse events in 17% of patients, the Day 28 mortality was 6%. Cumulative acquisition of CRGNO by Day 28 occurred in 4% of patients in the meropenem and 12% in the SOC arm (p = 0.052). CONCLUSIONS: Within this study population, we found no evidence that meropenem was superior to SOC in terms of success at TOC, short term hearing disturbances, safety or mortality were similar in both treatment arms but the study was underpowered to detect the planned effect. Meropenem treatment did not select for colonization with CRGNOs. We suggest that meropenem as broad-spectrum antibiotic should be reserved for neonates who are more likely to have Gram-negative LOS, especially in NICUs where microorganisms producing extended spectrum- and AmpC type beta-lactamases are circulating

A Randomized Controlled Trial of Changes in Fluid Distribution across Menstrual Phases with Creatine Supplementation

This study examined the effects of creatine (Cr) loading on body mass (BM) and fluid markers of total body water (TBW), extra-cellular fluid (ECF), and intra-cellular fluid (ICF) across the menstrual cycle (MC). Thirty moderately active females, either naturally-menstruating (NM) or using hormonal contraceptives (HC), were randomized to Cr (Cr; 4 × 5 g/day of creatine monohydrate for 5 days; n = 15) or a non-caloric placebo (PL; n = 15) using a double-blind, placebo-controlled design, with a menstrual phase crossover. BM, TBW, ECF, and ICF were measured at pre- and post-supplementation in randomized order of follicular phase (FP; NM: MC days 0–8, HC: inactive pill days) or luteal phase (LP; NM: ≤15 days from next projected cycle start date, HC: active pill days) using bioelectrical impedance spectroscopy. Acute hydration status and salivary estrogen were used as covariates. Change in BM was not different between groups across MC ([PL-Cr] Δ 0.40 ± 0.50 kg; p = 0.427) or between MC phase across groups ([FP-LP] Δ 0.31 ± 0.48 kg; p = 0.528). TBW (p = 0.802), ECF (p = 0.373), and ICF (p = 0.795) were not different between supplement groups at pre-supplementation/FP time points. There were no significant differences between the NM and HC subjects at any time point, for any outcome (p > 0.05). Following LP supplementation, significant changes were observed in TBW (Cr: Δ 0.83 ± 0.38 L, PL: Δ −0.62 ± 0.38 L; p = 0.021), ECF (Cr: Δ 0.46 ± 0.15 L, PL: Δ −0.19 ± 0.15 L; p = 0.013), and ICF (Cr: Δ 0.74 ± 0.23 L, PL: Δ −0.02 ± 0.23 L; p = 0.041). These data demonstrate an increase in all fluid compartments in the LP following Cr loading, without observed alterations in body weight for females

The Local Bias Model in the Large Scale Halo Distribution

We explore the biasing in the clustering statistics of halos as compared to dark matter (DM) in simulations. We look at the second and third order statistics at large scales of the (intermediate) MICEL1536 simulation and also measure directly the local bias relation h = f({\delta}) between DM fluctuations, {\delta}, smoothed over a top-hat radius Rs at a point in the simulation and its corresponding tracer h (i.e. halos) at the same point. This local relation can be Taylor expanded to define a linear (b1) and non-linear (b2) bias parameters. The values of b1 and b2 in the simulation vary with Rs approaching a constant value around Rs > 30 - 60 Mpc/h. We use the local relation to predict the clustering of the tracer in terms of the one of DM. This prediction works very well (about percent level) for the halo 2-point correlation {\xi}(r_12) for r_12 > 15 Mpc/h, but only when we use the biasing values that we found at very large smoothing radius Rs > 30 - 60 Mpc/h. We find no effect from stochastic or next to leading order terms in the f({\delta}) expansion. But we do find some discrepancies in the 3-point function that needs further understanding. We also look at the clustering of the smoothed moments, the variance and skewness which are volume average correlations and therefore include clustering from smaller scales. In this case, we find that both next to leading order and discreetness corrections (to the local model) are needed at the 10 - 20% level. Shot-noise can be corrected with a term {\sigma}e^2/n where {\sigma}e^2 < 1, i.e., always smaller than the Poisson correction. We also compare these results with the peak-background split predictions from the measured halo mass function. We find 5-10% systematic (and similar statistical) errors in the mass estimation when we use the halo model biasing predictions to calibrate the mass.Comment: Accepted in MNRAS. Compared to first version, the paper has been completely reorganised. New figures and content adde