Miracle-dz/UniFAR-FTUs huggingface dataset:
Strange Quark Stars in Binaries: Formation Rates, Mergers, and Explosive Phenomena

Recently, the possible coexistence of a first family composed of “normal” neutron stars (NSs) with a second family of strange quark stars (QSs) has been proposed as a solution of problems related to the maximum mass and to the minimal radius of these compact stellar objects. In this paper, we study the mass distribution of compact objects formed in binary systems and the relative fractions of quark and NSs in different subpopulations. We incorporate the strange QS formation model provided by the two-families scenario, and we perform a large-scale population synthesis study in order to obtain the population characteristics. According to our results, the main channel for strange QS formation in binary systems is accretion from a secondary companion on an NS. Therefore, a rather large number of strange QSs form by accretion in low-mass X-ray binaries and this opens the possibility of having explosive GRB-like phenomena not related to supernovae and not due to the merger of two NSs. The number of double strange QS systems is rather small, with only a tiny fraction that merge within a Hubble time. This drastically limits the flux of strangelets produced by the merger, which turns out to be compatible with all limits stemming from Earth and lunar experiments. Moreover, this value of the flux rules out at least one relevant channel for the transformation of all NSs into strange QSs by strangelets’ absorption.
Insights on the Spectral Signatures of Stellar Activity and Planets from PCA

Photospheric velocities and stellar activity features such as spots and faculae produce measurable radial velocity signals that currently obscure the detection of sub-meter-per-second planetary signals. However, photospheric velocities are imprinted differently in a high-resolution spectrum than are Keplerian Doppler shifts. Photospheric activity produces subtle differences in the shapes of absorption lines due to differences in how temperature or pressure affects the atomic transitions. In contrast, Keplerian Doppler shifts affect every spectral line in the same way. With a high enough signal-to-noise (S/N) and resolution, statistical techniques can exploit differences in spectra to disentangle the photospheric velocities and detect lower-amplitude exoplanet signals. We use simulated disk-integrated time-series spectra and principal component analysis (PCA) to show that photospheric signals introduce spectral line variability that is distinct from that of Doppler shifts. We quantify the impact of instrumental resolution and S/N for this work.
Neutron star–axion star collisions in the light of multimessenger astronomy

Axions are increasingly favoured as a candidate particle for the dark matter in galaxies, since they satisfy the observational requirements for cold dark matter and are theoretically well motivated. Fluctuations in the axion field give rise to stable localised overdensities known as axion stars, which, for the most massive, compact cases, are potential neutron star mimickers. In principle, there are no fundamental arguments against the multi-messenger observations of GW170817/GRB170817A/AT2017gfo arising from the merger of a neutron star with a neutron star mimicker, rather than from a binary neutron star. To constrain this possibility and better understand the astrophysical signatures of a neutron star--axion star (NSAS) merger, we present in this work a detailed example case of a NSAS merger based on full 3D numerical relativity simulations, and give an overview of the many potential observables - ranging from gravitational waves, to optical and near-infrared electromagnetic signals, radio flares, fast radio bursts, gamma ray bursts, and neutrino emission. We discuss the individual channels and estimate to which distances current and future observatories might be able to detect such a NSAS merger. Such signals could constrain the unknown axion mass and its couplings to standard baryonic matter,thus enhancing our understanding of the dark matter sector of the Universe.
MHD Study of Extreme Space Weather Conditions for Exoplanets With Earth‐Like Magnetospheres: On Habitability Conditions and Radio‐Emission

The present study aims at characterizing the habitability conditions of exoplanets with an Earth‐like magnetosphere inside the habitable zone of M and F stars, caused by the direct deposition of the stellar wind on the exoplanet surface. Also, the radio emission generated by exoplanets with a Earth‐like magnetosphere is calculated for different space weather conditions. The study is based on a set of MHD simulations performed by the code PLUTO. Exoplanets hosted by M stars at 0.2 au are protected from the stellar wind during regular and coronal mass ejection (CME)‐like space weather conditions if the star rotation period is slower than 3 days. Exoplanets hosted by a F stars at ≥2.5 au are protected during regular space weather conditions, but a stronger magnetic field compared to the Earth is mandatory if the exoplanet is close to the inner edge of the star habitable zone (2.5 au) during CMEs. The range of radio emission values calculated in the simulations are consistent with the scaling proposed by Zarka (2018, https://doi.org/10.1007/978-3-319-55333-7_22) during regular and common CME‐like space weather conditions. If the radio telescopes measure a relative low radio emission signal with small variability from an exoplanet, that may indicate favorable exoplanet habitability conditions. The radio emission power calculated for exoplanets with an Earth‐like magnetosphere is in the range of 3 × 107 to 2 × 1010 W for SW dynamic pressures between 1.5 and 100 nPa and interplanetary magnetic field intensities between 50 and 250 nT, and is below the sensitivity threshold of present radio telescopes at parsec distances.
Mean Hematocrit Values, Disease Severity, and Discharge Status of Undernourished Versus Well-Nourished Children with Dengue Infection in a Tertiary Government Hospital

Background: Studies comparing hematocrit values, disease severity, and discharge status between well-nourished and undernourished pediatric dengue patients are limited. Objective: This study compared the mean hematocrit values, disease severity and discharge status of undernourished vs. well-nourished pediatric dengue patients admitted in a tertiary government hospital. Methodology: A retrospective cohort study involving 114 pediatric dengue patients, with comparison groups of well-nourished and undernourished children matched according to age, phase of illness and sex was done. Main outcomes measured were mean hematocrit values, disease severity and discharge status. Results: There was a significantly lower mean pre-resuscitation hematocrit in the wasted (M=39.67%, SD=3.78) compared to the well-nourished group (M=43.68%, SD=4.72), p=0.006, among children >6 to 12 years old in the febrile phase. There were no significant differences in disease severity and discharge status between wasted and well-nourished children. In those >2 to 6 years old in the febrile phase, the severely wasted had significantly higher pre-resuscitation hematocrit (M=43.28%, SD=4.77) compared to well-nourished children (M=39.11%, SD=5.34), p=0.041. More severe dengue, worse discharge status and an earlier time to demise was seen among severely wasted children. Conclusion: Wasted participants had significantly lower mean hematocrit values with no difference in disease severity and discharge status when compared to well-nourished participants. Severely wasted children had significantly higher hematocrit values, severe dengue, and worse discharge status.
FR0CAT: a FIRST catalog of FR0 radio galaxies

With the aim of exploring the properties of the class of FR0 radio galaxies, we selected a sample of 108 compact radio sources, called FR0CAT, by combining observations from the NVSS, FIRST, and SDSS surveys. The catalog includes sources with z$\leq 0.05$, with a radio size $\lesssim$ 5 kpc, and with an optical spectrum characteristic of low-excitation galaxies. Their 1.4-GHz radio luminosities range $10^{38} \lesssim \nu L_{1.4} \lesssim 10^{40}$ erg/s. The FR0CAT hosts are mostly (86%) luminous ($-21 \gtrsim M_r \gtrsim -23$) red early-type galaxies with black hole masses $10^8 \lesssim M_{\rm BH} \lesssim 10^9 M_\odot$: similar to the hosts of FRI radio galaxies, but they are on average a factor $\sim$1.6 less massive. The number density of FR0CAT sources is $\sim$5 times higher than that of FRIs, and thus they represent the dominant population of radio sources in the local Universe. Different scenarios are considered to account for the smaller sizes and larger abundance of FR0s with respect to FRIs. An age-size scenario that considers FR0s as young radio galaxies that will all eventually evolve into extended radio sources cannot be reconciled with the large space density of FR0s. However, the radio activity recurrence, with the duration of the active phase covering a wide range of values and with short active periods strongly favored with respect to longer ones, might account for their large density number. Alternatively, the jet properties of FR0s might be intrinsically different from those of the FRIs, the former class having lower bulk Lorentz factors, possibly due to lower black hole spins. Our study indicates that FR0s and FRI/IIs can be interpreted as two extremes of a continuous population of radio sources that is characterized by a broad distribution of sizes and luminosities of their extended radio emission, but shares a single class of host galaxies.
Relativity, anomalies and objectivity loophole in recent tests of local realism

Abstract Local realism is in conflict with special quantum Bell-type models. Recently, several experiments have demonstrated violation of local realism if we trust their setup assuming special relativity valid. In this paper we question the assumption of relativity, point out not commented anomalies and show that the experiments have not closed objectivity loophole because clonability of the result has not been demonstrated. We propose several improvements in further experimental tests of local realism make the violation more convincing.
Stochastic approach to non-equilibrium quantum spin systems

We investigate a stochastic approach to non-equilibrium quantum spin systems based on recent insights linking quantum and classical dynamics. Exploiting a sequence of exact transformations, quantum expectation values can be recast as averages over classical stochastic processes. We illustrate this approach for the quantum Ising model by extracting the Loschmidt amplitude and the magnetization dynamics from the numerical solution of stochastic differential equations. We show that dynamical quantum phase transitions following quantum quenches from the ferromagnetic ground state are accompanied by signatures in the classical distribution functions, including enhanced fluctuations. We demonstrate that the method is capable of handling integrable and non-integrable problems in a unified framework, including those in higher dimensions.
Wide-Field CCD Photometry of the Globular Cluster M92

We present wide-field CCD photometry of the Galactic globular cluster M92 obtained in the V and I bands with the CFH12K mosaic CCD at the Canada-France-Hawaii Telescope. A well-defined color-magnitude diagram is derived down to 5 mag fainter than the cluster main-sequence turnoff. After removing the background contribution, we obtain luminosity and mass functions, surface density profiles, and the surface number density maps of the stars belonging to the cluster. The surface density profile of all stars shows that the cluster's halo extends at least out to ∼30′ from the cluster center, in agreement with previous study, but the profile of faint stars at the very outer region of the cluster shows a different gradient compared with that of bright stars. For a mass function of the form Φ(M) ∝ M-(1+x), we find that the inner region (5′ < r < 9′) of the cluster has x ≃ 1.2 ± 0.2, whereas the outer region (9′ < r < 15′) has x ≃ 1.8 ± 0.3, clearly indicating a mass segregation of the cluster. An estimate of the photometric mass of the cluster implies that the remnant populations (white dwarfs and neutron stars) contribute at least 25% of the total cluster mass. The surface density map of M92 shows some evidence that the tidal tail of M92 may be oriented perpendicular to the direction toward the Galactic center.
ALMA Observations of the Gravitational Lens SDP.9

We present long-baseline ALMA observations of the strong gravitational lens H-ATLAS J090740.0−004200 (SDP.9), which consists of an elliptical galaxy at lensing a background submillimeter galaxy into two extended arcs. The data include Band 6 continuum observations, as well as CO J = 6−5 molecular line observations, from which we measure an updated source redshift of . The image morphology in the ALMA data is different from that of the Hubble Space Telescope (HST) data, indicating a spatial offset between the stellar, gas, and dust component of the source galaxy. We model the lens as an elliptical power law density profile with external shear using a combination of archival HST data and conjugate points identified in the ALMA data. Our best model has an Einstein radius of and a slightly steeper than isothermal mass profile slope. We search for the central image of the lens, which can be used constrain the inner mass distribution of the lens galaxy including the central supermassive black hole, but do not detect it in the integrated CO image at a 3σ rms level of 0.0471 Jy km s−1.
Heat Transport by Phonons and Electrons

Efficient heat transport requires a sufficient number of collisions among energy carriers to take place. Mean free path can be thought of as the averaged distance traveled by the energy carrier per collision over a sufficient number of collisions. Mean free time, on the other hand, is the averaged time traveled by the energy carrier per collision over a sufficient number of collisions. The mean free path for the lattice is of the order of 10–10 nm. The mean free time for electron–electron, electron–phonon (for metals), and phonon–phonon (semiconductors, dielectric crystals, and insulators) collisions is of the order of 10 femtoseconds, 10 ps, and 10 ps, respectively. As the physical scale of a device shrinks to the order of the mean free path of the energy carriers (microscale effect in space), or the process time shortens into the range of their mean free time (microscale effect in time), individual and yet statistically meaningful behavior of the energy carriers becomes pronounced. The resulting behavior of heat transport in microscale will be very different from macroscale heat transfer based on the averages taken over hundreds of thousands of grains (in space) and collisions (in time). Different physical bases have been used in describing different types of energy carriers in microscale heat transfer. This chapter reviews most representative phonon–electron interaction (for metals) and phonon scattering (for semiconductors, dielectric crystals, and insulators) models in microscale heat transfer to exemplify the differences resulting from the development made on different physical bases. Special effort then follows to extract the commonalities among the differences, paving the way for the generalized dual-phase-lag model that will be deployed through the rest of the book. From a microscopic point of view, the process of heat transport is governed by phonon–electron interaction in metallic films and by phonon scattering in dielectric films, insulators, and semiconductors. Conventional theories established on the macroscopic level, such as heat diffusion assuming Fourier’s law, are not expected to be informative for microscale conditions because they describe macroscopic behavior averaged over many grains. This holds even more true should the transient behavior at extremely short times, say, of the order of picoseconds to femtoseconds, become major concerns. A typical example
A LARGE-SCALE SPECTROSCOPIC SURVEY OF METHANOL AND OH LINE EMISSION FROM THE GALACTIC CENTER: OBSERVATIONS AND DATA

Class I methanol masers are collisionally pumped and are generally correlated with outflows in star-forming sites in the Galaxy. Using the Very Large Array in its A-array configuration, we present a spectral line survey to identify methanol emission at 36.169 GHz. Over 900 pointings were used to cover a region 66′ × 13′ along the inner Galactic plane. A shallow survey of OH at 1612, 1665, 1667, and 1720 MHz was also carried out over the area covered by our methanol survey. We provide a catalog of 2240 methanol masers with narrow line-widths of ∼1 km s−1, spatial resolutions of , and rms noises ∼20 mJy beam−1 per channel. Lower limits on the brightness temperature range from 27,000 to 10,000,000 K, showing that the emission is of non-thermal origin. We also provide a list of 23 OH (1612), 14 OH (1665), 5 OH (1667), and 5 OH (1720 MHz) masers. The origin of such a large number of methanol masers is not clear. Many methanol masers appear to be associated with infrared dark clouds, though it appears unlikely that the entire population of these masers trace the early phase of star formation in the Galactic center.
Marital Status, Living Arrangements and Mortality at Older Ages in Chile, 2004–2016

The risk of mortality in old age is associated with marital status and living arrangements. There is still little knowledge about this in Latin America. Our objectives are to examine the association between marital status, living arrangements and mortality of older adults (>60 years) in Chile, and to test whether this association varies when demographic, socioeconomic and health factors are included. We used data from the Social Protection Survey, and mortality data were linked to the Civil Registry. We estimate a series of Poisson regression models. Our results show a clear association between marriage and longevity, since even controlling for demographic, socioeconomic and health factors, we found that separated or divorced, widowed, and unmarried people showed higher relative mortality compared to married people (IRR1.24, IRR1.33, IRR1.35, respectively). Considering only living arrangements, the results show that living alone, alone with children, with children and other relatives or in other arrangements is associated with higher mortality (IRR1.22, IRR1.27, IRR1.35, IRR1.35, respectively) compared to those living with their partners and children. However, considering marital status and living arrangements together, we find that survival among older adults was strongly associated with marital status. Marital status continues to be a direct measure of living arrangements among older adults in Chile.
Development and Validation of the Self-efficacy for Writing and Defending Academic Texts Scale1

Writing and defending a thesis is a requirement to earn a university degree. Previous findings indicate that self-efficacy is related to academic performance. However, no existing tools register students’ perception of efficacy towards writing and defining academic texts. Our purpose was to develop and validate such a scale. Scale scores content, structural, convergent, and criterion-related validity as well as the measurement invariance across sex was evaluated using data from 418 students from 23 Spanish universities. Our findings showed that the scale holds a unidimensional structure that is invariant across sex. Data also supported the convergent validity, with correlations with self-efficacy and anxiety measures. The scale could track the effect of an educational intervention designed to improve students’ writing and defending academic texts skills, and the scores were related to performance on a writing task. Norms are provided to facilitate the interpretation of the scale scores.
On the regularity of static axially symmetric solutions in SU(2) Yang-Mills dilaton theory

The regularity of static axially symmetric solutions in SU(2) Yang-Mills-dilaton theory is examined. We show that the solutions obtained previously within a singular Ansatz for the non-abelian gauge field can be gauge transformed into a regular form. The local form of the gauge transformation is given on the singular axis and at the origin.
nbodykit: An Open-source, Massively Parallel Toolkit for Large-scale Structure

We present nbodykit, an open-source, massively parallel Python toolkit for analyzing large-scale structure (LSS) data. Using Python bindings of the Message Passing Interface, we provide parallel implementations of many commonly used algorithms in LSS. nbodykit is both an interactive and scalable piece of scientific software, performing well in a supercomputing environment while still taking advantage of the interactive tools provided by the Python ecosystem. Existing functionality includes estimators of the power spectrum, two- and three-point correlation functions, a friends-of-friends grouping algorithm, mock catalog creation via the halo occupation distribution technique, and approximate N-body simulations via the FastPM scheme. The package also provides a set of distributed data containers, insulated from the algorithms themselves, that enables nbodykit to provide a unified treatment of both simulation and observational data sets. nbodykit can be easily deployed in a high-performance computing environment, overcoming some of the traditional difficulties of using Python on supercomputers. We provide performance benchmarks illustrating the scalability of the software. The modular, component-based approach of nbodykit allows researchers to easily build complex applications using its tools. The package is extensively documented at http://nbodykit.readthedocs. io, which also includes an interactive set of example recipes for new users to explore. As open-source software, we hope nbodykit provides a common framework for the community to use and develop in confronting the analysis challenges of future LSS surveys.
Mediating and Moderating Effects of Iron Homeostasis Alterations on Fetal Alcohol-Related Growth and Neurobehavioral Deficits

We have previously demonstrated prenatal alcohol exposure (PAE)-related alterations in maternal and infant iron homeostasis. Given that early iron deficiency and PAE both lead to growth restriction and deficits in recognition memory and processing speed, we hypothesized that PAE-related iron homeostasis alterations may mediate and/or moderate effects of PAE on growth and neurobehavior. We examined this hypothesis in a prenatally recruited, prospective longitudinal birth cohort [87 mother-infant pairs with heavy prenatal alcohol exposure (mean = 7.2 drinks/occasion on 1.4 days/week); 71 controls], with serial growth measures and infant neurobehavioral assessments. PAE was related to growth restriction at 2 weeks and 5 years, and, in infancy, poorer visual recognition memory, slower processing speed, lower complexity of symbolic play, and higher emotionality and shyness on a parental report temperament scale. Lower maternal hemoglobin-to-log(ferritin) ratio, which we have shown to be associated with PAE, appeared to exacerbate PAE-related 2-week head circumference reductions, and elevated maternal ferritin, which we have shown to be associated with PAE, appeared to exacerbate PAE-related visual recognition memory deficits. In causal inference analyses, PAE-related elevations in maternal ferritin and hemoglobin:log(ferritin) appeared to statistically mediate 22.6–82.3% of PAE-related growth restriction. These findings support potential mechanistic roles of iron homeostasis alterations in fetal alcohol spectrum disorders (FASD).