High-accuracy high-mass ratio simulations for binary neutron stars and their comparison to existing waveform models

The subsequent observing runs of the advanced gravitational-wave detector network will likely provide us with various gravitational-wave observations of binary neutron star systems. For an accurate interpretation of these detections, we need reliable gravitational-wave models. To test and to point out how existing models could be improved, we perform a set of high-resolution numerical-relativity simulations for four different physical setups with mass ratios $q$ = $1.25$, $1.50$, $1.75$, $2.00$, and total gravitational mass $M = 2.7M_\odot$ . Each configuration is simulated with five different resolutions to allow a proper error assessment. Overall, we find approximately 2nd order converging results for the dominant $(2,2)$, but also subdominant $(2,1)$, $(3,3)$, $(4,4)$ modes, while, generally, the convergence order reduces slightly for an increasing mass ratio. Our simulations allow us to validate waveform models, where we find generally good agreement between state-of-the-art models and our data, and to prove that scaling relations for higher modes currently employed for binary black hole waveform modeling also apply for the tidal contribution. Finally, we also test if the current NRTidal model to describe tidal effects is a valid description for high-mass ratio systems. We hope that our simulation results can be used to further improve and test waveform models in preparation for the next observing runs

Constructing binary neutron star initial data with high spins, high compactnesses, and high mass ratios

The construction of accurate and consistent initial data for various binary parameters is a critical ingredient for numerical relativity simulations of the compact binary coalescence. In this article, we present an upgrade of the pseudospectral SGRID code, which enables us to access even larger regions of the binary neutron star parameter space. As a proof of principle, we present a selected set of first simulations based on initial configurations computed with the new code version. In particular, we simulate two millisecond pulsars close to their breakup spin, highly compact neutron stars with masses at about $98\%$ of the maximum supported mass of the employed equation of state, and an unequal mass systems with mass ratios even outside the range predicted by population synthesis models ($q = 2.03$). The discussed code extension will help us to simulate previously unexplored binary configurations. This is a necessary step to construct and test new gravitational wave approximants and to interpret upcoming binary neutron star merger observations. When we construct initial data, one has to specify various parameters, such as a rotation parameter for each star. Some of these parameters do not have direct physical meaning, which makes comparisons with other methods or models difficult. To facilitate this, we introduce simple estimates for the initial spin, momentum, mass, and center of mass of each individual star

High-accuracy simulations of highly spinning binary neutron star systems

With an increasing number of expected gravitational-wave detections of binary neutron star mergers, it is essential that gravitational-wave models employed for the analysis of observational data are able to describe generic compact binary systems. This includes systems in which the individual neutron stars are millisecond pulsars for which spin effects become essential. In this work, we perform numerical-relativity simulations of binary neutron stars with aligned and anti-aligned spins within a range of dimensionless spins of $\chi \sim [-0.28,0.58]$. The simulations are performed with multiple resolutions, show a clear convergence order and, consequently, can be used to test existing waveform approximants. We find that for very high spins gravitational-wave models that have been employed for the interpretation of GW170817 and GW190425 are not capable of describing our numerical-relativity dataset. We verify through a full parameter estimation study in which clear biases in the estimate of the tidal deformability and effective spin are present. We hope that in preparation of the next gravitational-wave observing run of the Advanced LIGO and Advanced Virgo detectors our new set of numerical-relativity data can be used to support future developments of new gravitational-wave models

Elliptica: a new pseudo-spectral code for the construction of initial data

Numerical studies of the dynamics of gravitational systems, e.g., black hole-neutron star systems, require physical and constraint-satisfying initial data. In this article, we present the newly developed pseudo-spectral code Elliptica, an infrastructure for construction of initial data for various binary and single gravitational systems of all kinds. The elliptic equations under consideration are solved on a single spatial hypersurface of the spacetime manifold. Using coordinate maps, the hypersurface is covered by patches whose boundaries can adapt to the surface of the compact objects. To solve elliptic equations with arbitrary boundary condition, Elliptica deploys a Schur complement domain decomposition method with a direct solver. In this version, we use cubed sphere coordinate maps and the fields are expanded using Chebyshev polynomials of the first kind. Here, we explain the building blocks of Elliptica and the initial data construction algorithm for a black hole-neutron star binary system. We perform convergence tests and evolve the data to validate our results. Within our framework, the neutron star can reach spin values close to breakup with arbitrary direction, while the black hole can have arbitrary spin with dimensionless spin magnitude $\sim 0.8$

Effect of betaine supplementation on power performance and fatigue

<p>Abstract</p> <p>Background</p> <p>The purpose of this study was to examine the efficacy of 15 days of betaine supplementation on muscle endurance, power performance and rate of fatigue in active college-aged men.</p> <p>Methods</p> <p>Twenty-four male subjects were randomly assigned to one of two groups. The first group (BET; 20.4 ± 1.3 years; height: 176.8 ± 6.6 cm; body mass: 77.8 ± 13.4 kg) consumed the supplement daily, and the second group (PL; 21.4 ± 4.7 years; height: 181.3 ± 5.9 cm; body mass: 83.3 ± 5.2 kg) consumed a placebo. Subjects were tested prior to the onset of supplementation (T1) and 7 (T2) and 14 days (T3) following supplementation. Each testing period occurred over a 2-day period. During day one of testing subjects performed a vertical jump power (VJP) and a bench press throw (BPT) power test. In addition, subjects were required to perform as many repetitions as possible with 75% of their 1-RM in both the squat and bench press exercises. Both peak and mean power was assessed on each repetition. On day two of testing subjects performed two 30-sec Wingate anaerobic power tests (WAnT), each test separated by a 5-min active rest.</p> <p>Results</p> <p>No differences were seen at T2 or T3 in the repetitions performed to exhaustion or in the number of repetitions performed at 90% of both peak and mean power between the groups in the bench press exercise. The number of repetitions performed in the squat exercise for BET was significantly greater (p < 0.05) than that seen for PL at T2. The number of repetitions performed at 90% or greater of peak power in the squat exercise was significantly greater for BET at both T2 and T3 than PL. No differences in any power assessment (VJP, BPT, WAnT) was seen between the groups</p> <p>Conclusion</p> <p>Two-weeks of betaine supplementation in active, college males appeared to improve muscle endurance of the squat exercise, and increase the quality of repetitions performed.</p

Desorption isotherm model for a Malaysian rough rice variety (MR219)

Moisture desorption model of long grain Malaysian rough rice variety (MR219) was experimentally obtained using the static gravimetric method for different combinations of temperature (40, 45, 50, 55°C) and water activities (0.0507 to 0.9331). Five most commonly used models with three parameters namely modified Chung-Pfost, modified GAB, modified Halsey, modified Henderson and modified Oswin and a four parameters model (Zuritz et al., 1978) were determined for their ability to fit the experimental data using non linear regression techniques. Comparisons between all models were made on the basis of standard error of estimate (SEE), residual sum squares (RSS) and residual plots. Based on the results of this study, the Zuritz et al., modified Chung-Pfost and modified GAB models could be useful to predict the desorption EMC of MR219. The modified Halsey, modified Henderson and modified Oswin presented a poor fitting to the experimental data. In addition, the model by Zuritz et al. was found to be the most appropriate equation for representing the desorption isotherm model for MR219 at the range of temperatures from 40°C to 60°C

Thermogenic effect of meltdown RTD™ energy drink in young healthy women: a double blind, cross-over design study

This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens

The prevalence of depression among Iranian infertile couples: an update systematic review and meta-analysis

Background: Depression is a common mental disorder. Infertility can lead to depression. The current systematic review and meta-analysis were conducted to estimate the pooled prevalence of depression among Iranian infertile couples. Seven electronic databases (Google Scholar, MagIran, SID, Science Direct, PubMed, Scopus, Web of Science) were searched, up to August 2019, for relevant published studies. The pooled prevalence of depression also pooled mean of depression score was determined using a random-effects model with a 95 confidence interval (95 CI). All analyses performed using Stata ver11 (Stata Corporation, College Station, TX, USA). The 0.05 was considered a significant level. The main body: Totally, 230 studies were retrieved and 31 studies included in the meta-analysis. The pooled prevalence of depression among infertile couples was about 35.3 (95 CI 24.1�46.5), and the prevalence of depression among females and males was 48.7 (95 CI 24.0�73.3) and 9 (95 CI 0 to 23.7), respectively. Conclusions: Our findings suggest a high prevalence of depression in infertile couples. The results can highlight an important and growing mental disorder among infertile couples that may be overlooked. © 2020, The Author(s)

Chitosan-based Nanoparticles in Mucosal Vaccine Delivery

Most infectious diseases are caused by pathogenic infiltrations from the mucosal tract. Nowadays, the use of vaccines has been widely investigated for the prevention of different infectious diseases, infertility, immune disorders, malignancies, and allergies. Broad-spectrum adjuvant substances have been studied for immune system stimulation with a greater efficiency against specific antigens. Various adjuvants have been developed such as inorganic, oil-based, and emulsion adjuvants, bacterial products and their derivatives, cytokines, cytosine-guanine dinucleotide (CpG) motifs, and particulate systems. Mucosal vaccine delivery is an alternative route to induce both humoral and cellular immune responses. Applying nanoparticles in vaccine formulations allows not only improved antigen stability and immunogenicity, but also targeted delivery, and consequently, more specific release of the agent of interest. Chitosan nanoparticles have immunological activity and mucoadhesive properties. They have been used as a mucosal vaccine delivery system for many antigens. This review provides an overview of the recent advances in chitosan nanoparticles as a novel mucosal vaccine delivery system

Sediment tracing from the catchment to reef 2016 to 2018: Flood plume, marine sediment trap and logger data time series

The sediment dynamics at marine sites in the inshore GBRL region likely fall into three separate categories including sites where: 1. input of new terrigenous sediments have by far the greatest influence on sediment exposure and subsequent resuspension (e.g. Dunk Island, Orpheus Island, Havannah Island, Cleveland Bay?); 2. input of new terrigenous sediments are at least equivalent to resuspension events which likely increases upon larger river discharge events (e.g. Cleveland Bay?, Orchard Rocks). 3. input of new terrigenous sediments are less than or equal to common resuspension events (e.g. Middle Reef, Geoffrey Bay). This provides some of the first empirical data to support the findings of the satellite photic depth modelling of Fabricius et al. (2014, 2016) where the delivery of new terrigenous sediment considerably influences water clarity on the inshore Great Barrier Reef