355 research outputs found

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

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    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

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

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    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

    The Local Bias Model in the Large Scale Halo Distribution

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    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

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

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    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

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

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    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

    The impact of obesity on reproductive health and metabolism in reproductive-age females

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    Obesity is a highly prevalent chronic disease that impacts \u3e40% of reproductive-aged females. The pathophysiology of obesity is complex and can be understood simply as a chronic energy imbalance whereby caloric intake exceeds caloric expenditure with an energy surplus stored in adipose tissue. Obesity may be categorized into degrees of severity as well as different phenotypes on the basis of metabolic health and underlying pathophysiology. Obesity and excess adiposity have a significant impact on fertility and reproductive health, with direct effects on the hypothalamic-pituitary-ovarian axis, the ovary and oocyte, and the endometrium. There are significant adverse pregnancy outcomes related to obesity, and excess weight gain before, during, and after pregnancy that can alter the lifelong risk for metabolically unhealthy obesity. Given the high prevalence and pervasive impact of obesity on reproductive health, there is a need for better and individualized care for reproductive-aged females that considers obesity phenotype, underlying pathophysiology, and effective and sustainable interventions to treat obesity and manage weight gain before, during, and after pregnancy

    A compendium of chameleon constraints

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    The chameleon model is a scalar field theory with a screening mechanism that explains how a cosmologically relevant light scalar can avoid the constraints of intra-solar-system searches for fifth-forces. The chameleon is a popular dark energy candidate and also arises in f(R) theories of gravity. Whilst the chameleon is designed to avoid historical searches for fifth-forces it is not unobservable and much effort has gone into identifying the best observables and experiments to detect it. These results are not always presented for the same models or in the same language, a particular problem when comparing astrophysical and laboratory searches making it difficult to understand what regions of parameter space remain. Here we present combined constraints on the chameleon model from astrophysical and laboratory searches for the first time and identify the remaining windows of parameter space. We discuss the implications for cosmological chameleon searches and future small-scale probes

    Precision Nutrition for Management of Cardiovascular Disease Risk during Menopause

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    Background:Women can spend up to 40%of their lives in the postmenopausal state. As women begin to transition into menopause, known as perimenopause, changes in hormonal concentrations and body composition dramatically increase overall cardiometabolic risk. Dietary patterns and interventions can be utilized to prevent and treat cardiovascular disease (CVD) and some dietary patterns over others may be more beneficial due to their specific effects on the health aspects of menopause. In this narrative review, we summarize key cardiovascular alterations that occur during the menopause transition and explore current dietary recommendations to address CVD risk aswell as explore the newfrontier of precision nutrition and the implications for nutrition prescription during menopause. Summary: Popular dietary interventions for CVD such as the Dietary Approaches to Stop Hypertension (DASH) diet and the Mediterranean diet (MED) have limited data in women following menopause. However, both diets improve CVD risk biomarkers of total cholesterol and low-density lipoprotein cholesterol as well as lower oxidative stress and inflammation and improve endothelial function. As the menopause transition increases the risk for developing metabolic syndrome, insulin insensitivity, and dyslipidemia, the DASH diet and MED may be impactful dietary strategies for mediating CVD risk in menopausal women. However, these are one-size-fits-all approaches that neglect individual characteristics such as genetic predisposition and environmental factors. Precision nutrition considers individual factors for nutrition prescription, spanning from evaluating food intake preferences and behaviors to deep phenotyping. Data from a large-scale investigation of the menopause transition suggests nutritional strategies that address postprandial glycemic responses, and the gut microbiome may attenuate some of the unfavorable effects of menopause on CVD risk factors. Key Messages: Considering menopause, women are a clinical population that would greatly benefit from precision nutrition. Future research should explore the use of machine learning and artificial intelligence in a precision nutrition framework to modify the DASH diet and MED to address adverse effects that occur during the menopause transition are vital for supporting women\u27s health as they age
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