Miracle-dz/UniFAR-FTUs huggingface dataset:
Structure evolution of vacancy-hydrogen complexes in a nickel-based single-crystal superalloy

ABSTRACT The structural stability of vacancy-hydrogen complexes at the interface in nickel-based single-crystal superalloy is accessed mainly by calculating the activation energies associated with the evolution of their structures. It is found that the structure evolution and subsequent decomposition of the complex needs little time to be thermally activated at the service temperature of an aeroengine, and misfit dislocations at the interface significantly reduces the energy barrier for decomposition. Therefore, during the creep process, which is more severe at high temperatures, vacancies around misfit dislocations are not expected to enhance hydrogen interfacial segregation, although vacancy-hydrogen complexes are quite stable at room temperature.
A systematic review of school-based positive psychology interventions to foster teacher wellbeing

ABSTRACT Previous research into approaches to support the wellbeing of teachers have been informative in understanding the sources of stress and burnout, and, strategies to help teachers cope with the demands of the profession. However, less research has focused on approaches that promote wellbeing in a proactive and preventative way, a notion captured by the field of positive psychology. This study aimed to explore how school-based positive psychology interventions are delivered to foster teacher wellbeing, drawing on evidence from ten studies in a qualitative systematic review. The results indicated that interventions included mindfulness-based, multi-modal programs, and, gratitude interventions. All reported outcomes were positive, with some findings indicating that the structure of the interventions was as important to success as the content of the programs. Six common core elements were identified, including voluntary participation, the use of multiple methods, context-specific design, group format, professional instructors, and, weekly sessions. Based on the exisiting literature and an emphasis on common unifying findings, this review highlights the potential of positive psychology interventions in supporting teacher wellbeing by providing practical insights for schools, teacher educators, and, policymakers.
POPULATION III GAMMA-RAY BURST AFTERGLOWS: CONSTRAINTS ON STELLAR MASSES AND EXTERNAL MEDIUM DENSITIES

Population (Pop.) III stars are theoretically expected to be prominent around redshifts z ∼ 20, consisting of mainly very massive stars with M* ≳ 100 M☉, though there is no direct observational evidence for these objects. They may produce collapsar gamma-ray bursts (GRBs), with jets driven by magnetohydrodynamic processes, whose total isotropic-equivalent energy could be as high as Eiso ≳ 1057 erg over a cosmological-rest-frame duration of td ≳ 104 s, depending on the progenitor mass. Here, we calculate the afterglow spectra of such Pop. III GRBs based on the standard external shock model and show that they will be detectable with the Swift Burst Alert Telescope (BAT)/XRT and Fermi Large Area Telescope (LAT) instruments. We find that in some cases a spectral break due to electron–positron pair creation will be observable in the LAT energy range, which can put constraints on the ambient density of the pre-collapse Pop. III star. Thus, high-redshift GRB afterglow observations could be unique and powerful probes of the properties of Pop. III stars and their environments. We examine the trigger threshold of the BAT instrument in detail, focusing on the image trigger system, and show that the prompt emission of Pop. III GRBs could also be detected by BAT. Finally we briefly show that the late-time radio afterglows of Pop. III GRBs for typical parameters, despite the large distances, can be very bright: ≃ 140 mJy at 1 GHz, which may lead to a constraint on the Pop. III GRB rate from the current radio survey data, and ≃ 2.4 mJy at 70 MHz, which implies that Pop. III GRB radio afterglows could be interesting background source candidates for 21 cm absorption line detections.
Extending spin coherence times of diamond qubits by high-temperature annealing

Spins of negatively charged nitrogen-vacancy (NV$^-$) defects in diamond are among the most promising candidates for solid-state qubits. The fabrication of quantum devices containing these spin-carrying defects requires position-controlled introduction of NV$^-$ defects having excellent properties such as spectral stability, long spin coherence time, and stable negative charge state. Nitrogen ion implantation and annealing enable the positioning of NV$^-$ spin qubits with high precision, but to date, the coherence times of qubits produced this way are short, presumably because of the presence of residual radiation damage. In the present work, we demonstrate that a high temperature annealing at 1000$^\circ$C allows 2 millisecond coherence times to be achieved at room temperature. These results were obtained for implantation-produced NV$^-$ defects in a high-purity, 99.99% $^{12}$C enriched single crystal chemical vapor deposited diamond. We discuss these remarkably long coherence times in the context of the thermal behavior of residual defect spins. [Published in Physical Review B {\bf{88}}, 075206 (2013)]
STAR-FORMING GAS IN YOUNG CLUSTERS

Initial conditions for star formation in clusters are estimated for protostars whose masses follow the initial mass function from 0.05 to 10 solar masses. Star-forming infall is assumed equally likely to stop at any moment, due to gas dispersal dominated by stellar feedback. For spherical infall, the typical initial condensation must have a steep density gradient, as in low-mass cores, surrounded by a shallower gradient, as in the clumps around cores. These properties match observed column densities in cluster-forming regions when the mean infall stopping time is 0.05 Myr and the accretion efficiency is 0.5. The infall duration increases with final protostar mass, from 0.01 to 0.3 Myr, and the mass accretion rate increases from 3 to 300 × 10−6 solar masses yr−1. The typical spherical accretion luminosity is ∼5 solar luminosities, reducing the “luminosity problem” to a factor of ∼3. The initial condensation density gradient changes from steep to shallow at radius 0.04 pc, enclosing 0.9 solar masses, with mean column density 2 × 1022 cm−2 and with effective central temperature 16 K. These initial conditions are denser and warmer than those for isolated star formation.
Rare $B$ decays using lattice QCD form factors

In this write-up we review and update our recent lattice QCD calculation of $B \to K^*$, $B_s \to \phi$, and $B_s \to K^*$ form factors [arXiv:1310.3722]. These unquenched calculations, performed in the low-recoil kinematic regime, provide a significant improvement over the use of extrapolated light cone sum rule results. The fits presented here include further kinematic constraints and estimates of additional correlations between the different form factor shape parameters. We use these form factors along with Standard Model determinations of Wilson coefficients to give Standard Model predictions for several observables [arXiv:1310.3887]. The modest improvements to the form factor fits lead to improved determinations of $F_L$, the fraction of longitudinally polarized vector mesons, but have little effect on most other observables.
CHROMOSPHERIC VARIABILITY IN SLOAN DIGITAL SKY SURVEY M DWARFS. II. SHORT-TIMESCALE Hα VARIABILITY

We present the first comprehensive study of short-timescale chromospheric Hα variability in M dwarfs using the individual 15 minute spectroscopic exposures for 52, 392 objects from the Sloan Digital Sky Survey. Our sample contains about 103–104 objects per spectral type bin in the range M0–M9, with a typical number of three exposures per object (ranging up to a maximum of 30 exposures). Using this extensive data set, we find that about 16% of the sources exhibit Hα emission in at least one exposure, and of those about 45% exhibit Hα emission in all of the available exposures. As in previous studies of Hα activity (LHα/Lbol), we find a rapid increase in the fraction of active objects from M0–M6. However, we find a subsequent decline in later spectral types that we attribute to our use of the individual spectra. Similarly, we find saturated activity at a level of LHα/Lbol ≈ 10−3.6 for spectral types M0–M5 followed by a decline to about 10−4.3 in the range M7–M9. Within the sample of objects with Hα emission, only 26% are consistent with non-variable emission, independent of spectral type. The Hα variability, quantified in terms of the ratio of maximum to minimum Hα equivalent width (REW), exhibits a rapid rise from M0 to M5, followed by a plateau and a possible decline in M9 objects. In particular, variability with REW ≳ 10 is only observed in objects later than M5, and survival analysis indicates a probability of ≲0.1% that the REW values for M0–M4 and M5–M9 are drawn from the same distribution. We further find that for an exponential distribution, the REW values follow N(REW) ∝ exp[ − (REW − 1)/2.3] for M0–M4 and ∝exp[ − (REW − 1)/2.9] for M5–M9. Finally, comparing objects with persistent and intermittent Hα emission, we find that the latter exhibit greater variability. Based on these results, we conclude that Hα variability in M dwarfs on timescales of 15 minutes to 1 hr increases with later spectral type, and that the variability is larger for intermittent sources.
Gender, Religion, and Employment: How LDS Working Women Navigate Familial Conflict Concerning Their Paid Work

ABSTRACT Employment practices in America demonstrate one area in which gender theory provides a framework for understanding women’s economic behaviors and their families’ responses to their employment status. Religion has often functioned as a determinant of gender roles and employment practices. The present study explored the intersection of gender, religion, and female employment by focusing on a population with high levels of religiosity, women who are members of the Church of Jesus Christ of Latter-day Saints (LDS), also known as Mormons. While highly educated, LDS women are less likely to work due to religiously prescribed gender roles. This study specifically examined how LDS women navigate familial conflict concerning their paid work. An online survey solicited detailed responses from 215 LDS women. The author used a grounded theory methodology to analyze the data and develop a model for understanding how LDS women and their families navigate conflict concerning a woman’s paid work. The resulting theory describes the influence of religion on decision-making processes and management of conflict regarding women’s paid work. Most importantly, the study reveals the powerful role of religion in determining beliefs about gender roles and its influence on women’s fight for equality within faith communities and within families.
Kinetics of diffusion-controlled annihilation with sparse initial conditions

We study diffusion-controlled single-species annihilation with sparse initial conditions. In this random process, particles undergo Brownian motion, and when two particles meet, both disappear. We focus on sparse initial conditions where particles occupy a subspace of dimension δ that is embedded in a larger space of dimension d. We find that the co-dimension Δ = d − δ governs the behavior. All particles disappear when the co-dimension is sufficiently small, Δ ≤ 2; otherwise, a finite fraction of particles indefinitely survive. We establish the asymptotic behavior of the probability S(t) that a test particle survives until time t. When the subspace is a line, δ = 1, we find inverse logarithmic decay, S ∼ ( ln t ) − 1 , in three dimensions, and a modified power-law decay, S ∼ ( ln t ) t − 1 / 2 , in two dimensions. In general, the survival probability decays algebraically when Δ < 2, and there is an inverse logarithmic decay at the critical co-dimension Δ = 2.
Journal of Quantitative Analysis in Sports

We present evidence, based on play-by-play data from all 6087 games from the 2006/07– 2009/10 seasons of the National Basketball Association (NBA), that basketball scoring is well described by a continuous-time anti-persistent random walk. The time intervals between successive scoring events follow an exponential distribution, with essentially no memory between different scoring intervals. By including the heterogeneity of team strengths, we build a detailed computational random-walk model that accounts for a variety of statistical properties of scoring in basketball games, such as the distribution of the score difference between game opponents, the fraction of game time that one team is in the lead, the number of lead changes in each game, and the season win/loss records of each team.
On the Scatter of the Present-day Stellar Metallicity–Mass Relation of Cluster Dwarf Galaxies

We examine the scatter of the relation between stellar mass and stellar metallicity for cluster dwarf galaxies in the cosmological simulation Illustris. The mass-metallicity relation exhibits the smallest intrinsic scatter at the galaxies' times of peak stellar mass, suggesting stellar mass stripping to be the primary effect responsible for the rather broad relation at present. However, for about 40% of galaxies in the high-metallicity tail of the relation, we find mass stripping to coincide with an increased enrichment of stellar metallicity, possibly caused by the stripping of low-metallicity stars in the galaxy outskirts.
Stirring N-body systems: universality of end states

We study the evolution of the phase space of collisionless N-body systems under repeated stirrings or perturbations. We find convergence towards a limited solution group, in accordance with Hansen, Juncher & Sparre, that is independent of the initial system and environmental conditions, paying particular attention to the assumed gravitational paradigm (Newtonian and Modified Newtonian Dynamics). We examine the effects of changes to the perturbation scheme and in doing so identify a large group of perturbations featuring radial orbit instability which always lead to convergence. The attractor is thus found to be a robust and reproducible effect under a variety of circumstances.
Convergence rates for linear and nonlinear inverse problems in Hilbert spaces via Holder stability estimates

In this article, we look for a new kind of smoothness concept, i.e. the Holder stability estimates for determination of convergence rates of Tikhonov regularization for linear and non-linear inverse problems in Hilbert spaces. For linear inverse problems, we obtain the convergence rates without the use of the classical concept of spectral theory and for non-linear inverse problems, we obtain the results by incorporating both Holder stability estimates as well as the inhomogeneous variational inequality. We also consider Lavrentiev's regularization method for non-linear inverse problems in Hilbert spaces and find the convergence rates of its regularized solutions by incorporating Holder stability estimates as well as inhomogeneous variational inequality. The co-action between the variational inequalities and the Holder stability estimates is also discussed for both linear and non-linear inverse problems.
Estimating Distance from Parallaxes. IV. Distances to 1.33 Billion Stars in Gaia Data Release 2

For the vast majority of stars in the second Gaia data release, reliable distances cannot be obtained by inverting the parallax. A correct inference procedure must instead be used to account for the nonlinearity of the transformation and the asymmetry of the resulting probability distribution. Here, we infer distances to essentially all 1.33 billion stars with parallaxes published in the second Gaia data release. This is done using a weak distance prior that varies smoothly as a function of Galactic longitude and latitude according to a Galaxy model. The irreducible uncertainty in the distance estimate is characterized by the lower and upper bounds of an asymmetric confidence interval. Although more precise distances can be estimated for a subset of the stars using additional data (such as photometry), our goal is to provide purely geometric distance estimates, independent of assumptions about the physical properties of, or interstellar extinction toward, individual stars. We analyze the characteristics of the catalog and validate it using clusters. The catalog can be queried using ADQL at http://gaia.ari. uni-heidelberg.de/tap.html (which also hosts the Gaia catalog) and downloaded from http://www.mpia. de/~calj/gdr2_distances. html.
DETAILED DECOMPOSITION OF GALAXY IMAGES. II. BEYOND AXISYMMETRIC MODELS

We present a two-dimensional (2D) fitting algorithm (Galfit, ver. 3) with new capabilities to study the structural components of galaxies and other astronomical objects in digital images. Our technique improves on previous 2D fitting algorithms by allowing for irregular, curved, logarithmic and power-law spirals, ring, and truncated shapes in otherwise traditional parametric functions like the Sérsic, Moffat, King, Ferrer, etc., profiles. One can mix and match these new shape features freely, with or without constraints, and apply them to an arbitrary number of model components of numerous profile types, so as to produce realistic-looking galaxy model images. Yet, despite the potential for extreme complexity, the meaning of the key parameters like the Sérsic index, effective radius, or luminosity remains intuitive and essentially unchanged. The new features have an interesting potential for use to quantify the degree of asymmetry of galaxies, to quantify low surface brightness tidal features beneath and beyond luminous galaxies, to allow more realistic decompositions of galaxy subcomponents in the presence of strong rings and spiral arms, and to enable ways to gauge the uncertainties when decomposing galaxy subcomponents. We illustrate these new features by way of several case studies that display various levels of complexity.
Nanofluid-based wick-type integrated solar still for improved diurnal and nocturnal distillate production

ABSTRACT In the present work, a novel “nanofluid-based wick-type integrated solar still” has been designed, fabricated, and tested under on-sun conditions to assess its diurnal and nocturnal performance characteristics. Herein, floating wicks were placed inside the basin of single slope-single basin solar still. Furthermore, the basin water was supplied with external thermal energy collected by a nanofluid-based volumetrically absorbing solar collector (NBVASC) during the sunshine hours (9 am to 6 pm) and from the solar pond during the non-sunshine hours. In essence, the benefits of volumetric as well as surface heating have been synergized to significantly enhance the distillate production rate. Volumetric or bulk heating allows for enhanced sensible heat storage in the NBVASC, and the presence of wicks in the still’s basin lends localized surface heating of basin water – thus considerably improving the evaporation rates. Rigorous on-sun testing of “nanofluid-based wick-type integrated solar still” showed significant improvements relative to the conventional solar still; distillate productivity and efficiency enhancements on the order of 111.1% and 89.9%, respectively, were recorded (with exergy efficiency of 3.40%).
JCMT POL-2 and ALMA Polarimetric Observations of 6000–100 au Scales in the Protostar B335: Linking Magnetic Field and Gas Kinematics in Observations and MHD Simulations

We present our analysis of the magnetic field structures from 6000 to 100 au scales in the Class 0 protostar B335 inferred from our James Clerk Maxwell telescope (JCMT) POL-2 observations and ALMA archival polarimetric data. To interpret the observational results, we perform a series of (non)ideal MHD simulations of the collapse of a rotating nonturbulent dense core, whose initial conditions are adopted to be the same as observed in B335, and generate synthetic polarization maps. The comparison of our JCMT and simulation results suggests that the magnetic field on a 6000 au scale in B335 is pinched and well aligned with the bipolar outflow along the east–west direction. Among all our simulations, the ALMA polarimetric results are best explained with weak magnetic field models having an initial mass-to-flux ratio of 9.6. However, we find that with a weak magnetic field, the rotational velocity on a 100 au scale and the disk size in our simulations are larger than the observational estimates by a factor of several. An independent comparison of our simulations and the gas kinematics in B335 observed with the SMA and ALMA favors strong magnetic field models with an initial mass-to-flux ratio smaller than 4.8. We discuss two possibilities resulting in the different magnetic field strengths inferred from the polarimetric and molecular-line observations: (1) overestimated rotational-to-gravitational energy in B335, and (2) additional contributions in the polarized intensity due to scattering on a 100 au scale.
Multi-Timeframe Algorithmic Trading Bots Using Thick Data Heuristics with Deep Reinforcement Learning

This article presents an augmented Artificial Intelligence (AI) algorithmic trading approach that combines Thick Data Heuristic (TDH), with Deep Reinforcement Learning (DRL), to successfully learn trading execution timing policies. Combining the augmented AI human trader's intuition and heuristics with DRL techniques to provide more focused drivers for trading order execution timing is explored in this study. In this research, the goal is to solve the sequential decision-making problem of AI for profitable day and swing trading order timing executions. Enabling trading bots with cognitive intelligence and common-sense heuristics will offer traders including automatic traders an insight to understand the day-to-day swing trading timeframes indicators and arrive at mature trading decision-making. This article examines the performance of bots with Nasdaq and NYSE stocks that have a strong catalyst (info. which increases directional momentum) to find that they outperform benchmark algorithmic trading approaches. The research illustrates to the reader how to combine TDH and Deep Q-networks (DQN) into a TDH-DQN augmented AI trading bot. The bot learns through test data to predict the optimal timing of order executions autonomously on idealized trading time series data.
Absolutely Maximally Entangled States: Existence and Applications

We investigate absolutely maximally entangled (AME) states, which are multipartite quantum states that are maximally entangled with respect to any possible bipartition. These strong entanglement properties make them a powerful resource for a variety of quantum information protocols. In this paper, we show the existence of AME states for any number of parties, given that the dimension of the involved systems is chosen appropriately. We prove the equivalence of AME states shared between an even number of parties and pure state threshold quantum secret sharing (QSS) schemes, and prove necessary and sufficient entanglement properties for a wider class of ramp QSS schemes. We further show how AME states can be used as a valuable resource for open-destination teleportation protocols and to what extend entanglement swapping generalizes to AME states.