Miracle-dz/UniFAR-FTUs huggingface dataset:
Tracing the formation history of galaxy clusters into the epoch of reionization

The large-scale overdensities of galaxies at z~2-7 known as protoclusters are believed to be the sites of cluster formation, and deep, wide survey projects such as the Large Synoptic Survey Telescope (LSST) and the Wide Field Infrared Survey Telescope (WFIRST) will deliver significant numbers of these interesting structures. Spectroscopic confirmation and interpretation of these targets, however, is still challenging, and will require wide-field multi-plexed spectroscopy on >20 m-class telescopes in the optical and near-infrared. In the coming decade, detailed studies of protoclusters will enable us, for the first time, to systematically connect these cluster progenitors in the early universe to their virialized counterparts at lower redshifts. This will allow us to address observationally the formation of brightest cluster galaxies and other cluster galaxy populations, the buildup of the intra-cluster light, the chemical enrichment history of the intra-cluster medium, and the formation and triggering of supermassive black holes in dense environments, all of which are currently almost exclusively approached either through the fossil record in clusters or through numerical simulations. Furthermore, at the highest redshifts (z~5-10), these large extended overdensities of star-forming galaxies are believed to have played an important role in the reionization of the universe, which needs to be tested by upcoming experiments. Theory and recent simulations also suggest important links between these overdensities and the formation of supermassive black holes, but observational evidence is still lacking. In this white paper we review our current understanding of this important phase of galaxy cluster history that will be explored by the next generation of large aperture ground-based telescopes GMT and TMT.
Density functional plus dynamical mean-field theory of the metal-insulator transition in early transition-metal oxides

The combination of density functional theory and single-site dynamical mean-field theory, using both Hartree and full continuous-time quantum Monte Carlo impurity solvers, is used to study the metal-insulator phase diagram of perovskite transition-metal oxides of the form $AB$O$_3$ with a rare-earth ion $A$=Sr, La, Y and transition metal $B$=Ti, V, Cr. The correlated subspace is constructed from atomiclike $d$ orbitals defined using maximally localized Wannier functions derived from the full $p$-$d$ manifold; for comparison, results obtained using a projector method are also given. Paramagnetic DFT+DMFT computations using full charge self-consistency along with the standard "fully localized limit" (FLL) double counting are shown to incorrectly predict that LaTiO$_3$, YTiO$_3$, LaVO$_3$ and SrMnO$_3$ are metals. A more general examination of the dependence of physical properties on the mean $p$-$d$ energy splitting, the occupancy of the correlated $d$ states, the double-counting correction, and the lattice structure demonstrates the importance of charge-transfer physics even in the early transition-metal oxides and elucidates the factors underlying the failure of the standard approximations. If the double counting is chosen to produce a $p$-$d$ splitting consistent with experimental spectra, single-site dynamical mean-field theory provides a reasonable account of the materials properties. The relation of the results to those obtained from "$d$-only" models in which the correlation problem is based on the frontier orbital $p$-$d$ antibonding bands is determined. It is found that if an effective interaction $U$ is properly chosen the $d$-only model provides a good account of the physics of the $d^1$ and $d^2$ materials.
Optimal GNSS-Based Passive SAR Large Field-of-View Imaging via Multistatic Configuration: Method and Experimental Validation

In terms of the global coverage provided by global navigation satellite system (GNSS) signals, radar images of a large field-of-view can be obtained via passive synthetic aperture radar (SAR) using these signals of opportunity. Usually, large field-of-view imaging is challenging using conventional SAR methods owing to the space-variant resolution. In addition, only a moderate range resolution can be provided by the GNSS transmitters in the passive SAR system. In this article, an optimal imaging method for a large field-of-view using GNSS-based passive SAR is proposed, which exploits the inherent multistatic nature of GNSS. At first, the spatial resolution of each scatterer in the observation area relative to each GNSS transmitter is calculated according to the geometry. Then, the selection of the transmitter set is modeled as an optimization problem, where the minimal resolution cell is used as the optimal criterion. After that, an evolutionary algorithm is applied to solve the optimization problem. Finally, the space-time combination of the echoes over a long dwell time concerning selected GNSS transmitters is performed to form the radar image with a minimal spatial resolution. The proposed method is extensively validated using two experimental datasets, where the passive radar consists of BeiDou satellites and a fixed receiver. The spatial resolution improvement and the large field-of-view imaging capability of the proposed method are forcefully demonstrated according to the experimental results.
Feasibility of an Upper Limb Strength Training Program in Persons with Spinal Cord Injury during Primary Rehabilitation—An Uncontrolled Interventional Study

Data concerning the outcomes of standardized strength-training programs in people with acute spinal cord injury (SCI) are scarce. The present study evaluated the feasibility and effects of a clinic-internal strength-training concept in people with paraplegia during the course of primary rehabilitation. For this purpose, participants followed a 10–12 week standardized supervised strength-training program (30 training sessions) during primary rehabilitation. At the beginning, 5–6 weeks and 10–12 weeks later, maximal strength based on indirect one-repetition maximum (1RM) measurements for two specific exercises (triceps press; horizontal rowing pull) was determined. Twelve out of 17 participants successfully completed the study. Maximal weights for 1RM significantly increased over the 10–12 week training program for the triceps press (+30%; p = 0.018) and the horizontal rowing pull (+41%; p = 0.008). Training compliance was 95%. Reasons for study exclusion were urgent surgery (n = 2), cardio-respiratory complications (n = 1), shoulder pain (n = 1) and a training compliance of less than 50% (n = 1). In conclusion, a supervised and standardized strength-training program during primary rehabilitation of people with paraplegia is feasible and leads to significant increases in maximal strength. Although study participants showed a high training compliance, factors such as medical complications may impede the proper implementation of a strength-training concept into daily clinical practice.
CECI N'EST PAS A GLOBULAR CLUSTER: THE METALLICITY DISTRIBUTION OF THE STELLAR SYSTEM TERZAN 5

We present new determinations of the iron abundance for 220 stars belonging to the stellar system Terzan 5 in the Galactic bulge. The spectra have been acquired with FLAMES at the Very Large Telescope of the European Southern Observatory and DEIMOS at the Keck II Telescope. This is by far the largest spectroscopic sample of stars ever observed in this stellar system. From this data set, a subsample of targets with spectra unaffected by TiO bands was extracted and statistically decontaminated from field stars. Once combined with 34 additional stars previously published by our group, a total sample of 135 member stars covering the entire radial extent of the system has been used to determine the metallicity distribution function of Terzan 5. The iron distribution clearly shows three peaks: a super-solar component at [Fe/H] ≃ 0.25 dex, accounting for ∼29% of the sample, a dominant sub-solar population at [Fe/H] ≃ −0.30 dex, corresponding to ∼62% of the total, and a minor (6%) metal-poor component at [Fe/H] ≃ −0.8 dex. Such a broad, multi-modal metallicity distribution demonstrates that Terzan 5 is not a genuine globular cluster but the remnant of a much more complex stellar system.
Using Conceptual Models in Agile Software Development: A Possible Solution to Requirements Engineering Challenges in Agile Projects

Studies on requirements engineering with Agile methods for software development have shown difficulties in managing the quality of the requirements and communicating with users. Some of these studies have proposed conceptual modeling as a solution to these problems. However, the effort that is required to create conceptual models conflicts with Agile values. In this paper, we propose an approach for using conceptual models in projects while adhering to Agile principles. This approach focuses on projects in which requirements are expressed as user stories that are the main artifacts of the requirements used for software development with Agile methods. First, the paper presents a literature review in which we have systematically searched for the challenges to requirements engineering with Agile methods. Next, we report on a survey study in which we interviewed 16 experts in the Agile methodology to confirm the identified challenges and find new ones that are not covered in the literature. Based on a thematic analysis of the challenges, we argue that most of them map to the two main purposes of using conceptual models in software development: improving communication and understanding requirements. To effectively use conceptual models in projects that use the Agile methodology, several conditions must be met, which we make explicit in the paper. The paper ends by illustrating how these conditions can be met demonstrating the models that can be automatically generated from a given set of user stories. This demonstration was subsequently used to obtain feedback from the experts on the perceived benefits of conceptual models in addressing the challenges of requirements engineering.
A radio-frequency sheath model for complex waveforms

Plasma sheaths driven by radio-frequency voltages occur in contexts ranging from plasma processing to magnetically confined fusion experiments. An analytical understanding of such sheaths is therefore important, both intrinsically and as an element in more elaborate theoretical structures. Radio-frequency sheaths are commonly excited by highly anharmonic waveforms, but no analytical model exists for this general case. We present a mathematically simple sheath model that is in good agreement with earlier models for single frequency excitation, yet can be solved for arbitrary excitation waveforms. As examples, we discuss dual-frequency and pulse-like waveforms. The model employs the ansatz that the time-averaged electron density is a constant fraction of the ion density. In the cases we discuss, the error introduced by this approximation is small, and in general it can be quantified through an internal consistency condition of the model. This simple and accurate model is likely to have wide application.
Analytical halo model of galactic conformity

We present a fully analytical halo model of colour-dependent clustering that incorporates the effects of galactic conformity in a halo occupation distribution (HOD) framework. The model, based on our previous numerical work, describes conformity through a correlation between the colour of a galaxy and the concentration of its parent halo, leading to a correlation between central and satellite galaxy colours at fixed halo mass. The strength of the correlation is set by a tunable `group quenching efficiency', and the model can separately describe group-level correlations between galaxy colour (1-halo conformity) and large scale correlations induced by assembly bias (2-halo conformity). We validate our analytical results using clustering measurements in mock galaxy catalogs, finding that the model is accurate at the 10-20 percent level for a wide range of luminosities and length scales. We apply the formalism to interpret the colour-dependent clustering of galaxies in the Sloan Digital Sky Survey (SDSS). We find good overall agreement between the data and a model that has 1-halo conformity at a level consistent with previous results based on an SDSS group catalog, although the clustering data require satellites to be redder than suggested by the group catalog. Within our modelling uncertainties, however, we do not find strong evidence of 2-halo conformity driven by assembly bias in SDSS clustering.
Acceptance of Online Mapping Technology among Older Adults: Technology Acceptance Model with Facilitating Condition, Compatibility, and Self-Satisfaction

The benefits of traveling for older adults are extensively supported in the literature. Online mapping technology (OMT) is one of the most widely used applications by people during traveling. This study aimed to obtain insight into the acceptance of OMT among older adults. Additionally, an OMT acceptance model for older adults was developed in this study by integrating facilitating condition (FC), compatibility (COM), and self-satisfaction (SS) into the technology acceptance model (TAM). In this study, structural equation modeling was applied to the test of the OMT acceptance model. This study adopted a cross-sectional structured questionnaire survey for collecting quantitative data from older adults in China. Four hundred and sixteen Chinese older adults were involved in this survey. This study found that TAM was useful to explain the OMT acceptance among older adults. Additionally, FC was confirmed to be a positive factor in determining the perceived ease of use, while COM and SS were found to positively influence perceived usefulness. The results of this study are helpful for OMT developers to design OMT and adopt measures to enhance the use of OMT among older adults, thereby increasing their travel frequency.
POPULATION III GAMMA-RAY BURSTS AND BREAKOUT CRITERIA FOR ACCRETION-POWERED JETS

We investigate the propagation of accretion-powered jets in various types of massive stars such as Wolf-Rayet stars, light Population III (Pop III) stars, and massive Pop III stars, all of which are the progenitor candidates of gamma-ray bursts (GRBs). We perform two-dimensional axisymmetric simulations of relativistic hydrodynamics, taking into account both the envelope collapse and the jet propagation (i.e., the negative feedback of the jet on the accretion). Based on our hydrodynamic simulations, we show for the first time that the accretion-powered jet can potentially break out relativistically from the outer layers of Pop III progenitors. In our simulations, the accretion rate is estimated by the mass flux going through the inner boundary, and the jet is injected with a fixed accretion-to-jet conversion efficiency η. By varying the efficiency η and opening angle θop for more than 40 models, we find that the jet can make a relativistic breakout from all types of progenitors for GRBs if a simple condition η ≳ 10−4(θop/8°)2 is satisfied, which is consistent with analytical estimates. Otherwise no explosion or some failed spherical explosions occur.
Cartesian currents in fractional Sobolev spaces and applications to functions of bounded higher variation

In this paper we establish weak continuity results for the distribution Jacobian minors in fractional sobolev spaces, which can be seen as a extension of recent work of Brezis and Nguyen on the distributional Jacobian determinant. Then we apply results to introduce the currents associated with graphs of maps in fractional Sobolev spaces and study some relevant properties such as structure properties, weak continuity and so on. As another application, we extend the definition of functions of bounded higher variation, which defined by Jerrard and Soner in $W^{1,N-1}\cap L^{\infty}(\Omega,\mathbb{R}^N)$ ( $\mbox{dim}\Omega\geq N$), to $W^{1-\frac{1}{N},N}(\Omega,\mathbb{R}^N)$ and give some results including weak coarea formula, strong coarea formula and chain rule.
‘Grandmother, aren’t you going to sing for us?’ Current childcare practices and caregivers’ perceptions of and receptivity to early childhood development activities in rural Burkina Faso

Introduction Effective stimulation and responsive caregiving during the first 2 years is crucial for children’s development. By age 3–4 years, over 40% of children in sub-Saharan Africa fail to meet basic cognitive or socioemotional milestones, but there are limited data on parenting and childcare practices. This study, conducted to inform the design of a mass media intervention, explored practices, perceptions, motivators and obstacles to childhood development-related practices among parents and caregivers of children aged 0–2 years in rural Burkina Faso. Methods We performed two rounds of six focus groups with 41 informants in two villages, using an adapted version of the Trials of Improved Practices methodology. These first explored beliefs and practices, then introduced participants to the principles and benefits of early childhood development (ECD) and provided illustrative examples of three practices (interactive ways of talking, playing and praising) to try with their children. One week later, further discussions explored participants’ experiences and reactions. Data were analysed inductively using thematic content analysis. Results Existing activities with young children were predominantly instructive with limited responsive interaction and stimulation. Participants were receptive to the practices introduced, noted positive changes in their children when they adopted these practices and found engagement with children personally rewarding. Conclusion Interactive, stimulating activities with young children did not appear to be widespread in the study area, but caregivers were receptive to information about the importance of early stimulation for children’s development. ECD messages should be tailored to the local sociocultural context and consider time limitations.
Alfvén Wave Turbulence as a Coronal Heating Mechanism: Simultaneously Predicting the Heating Rate and the Wave-induced Emission Line Broadening

We test the predictions of the Alfvén Wave Solar Model (AWSoM), a global wave-driven magnetohydrodynamic (MHD) model of the solar atmosphere, against high-resolution spectra emitted by the quiescent off-disk solar corona. AWSoM incorporates Alfvén wave propagation and dissipation in both closed and open magnetic field lines; turbulent dissipation is the only heating mechanism. We examine whether this mechanism is consistent with observations of coronal EUV emission by combining model results with the CHIANTI atomic database to create synthetic line-of-sight spectra, where spectral line widths depend on thermal and wave-related ion motions. This is the first time wave-induced line broadening is calculated from a global model with a realistic magnetic field. We used high-resolution SUMER observations above the solar west limb between 1.04 and 1.34 R⊙ at the equator, taken in 1996 November. We obtained an AWSoM steady-state solution for the corresponding period using a synoptic magnetogram. The 3D solution revealed a pseudo-streamer structure transversing the SUMER line of sight, which contributes significantly to the emission; the modeled electron temperature and density in the pseudo-streamer are consistent with those observed. The synthetic line widths and the total line fluxes are consistent with the observations for five different ions. Further, line widths that include the contribution from the wave-induced ion motions improve the correspondence with observed spectra for all ions. We conclude that the turbulent dissipation assumed in the AWSoM model is a viable candidate for explaining coronal heating, as it is consistent with several independent measured quantities.
THE PANCHROMATIC HUBBLE ANDROMEDA TREASURY. VI. THE RELIABILITY OF FAR-ULTRAVIOLET FLUX AS A STAR FORMATION TRACER ON SUBKILOPARSEC SCALES

We have used optical observations of resolved stars from the Panchromatic Hubble Andromeda Treasury to measure the recent (<500 Myr) star formation histories (SFHs) of 33 far-UV (FUV)-bright regions in M31. The region areas ranged from ∼104 to 106 pc2, which allowed us to test the reliability of FUV flux as a tracer of recent star formation on subkiloparsec scales. The star formation rates (SFRs) derived from the extinction-corrected observed FUV fluxes were, on average, consistent with the 100 Myr mean SFRs of the SFHs to within the 1σ scatter. Overall, the scatter was larger than the uncertainties in the SFRs and particularly evident among the smallest regions. The scatter was consistent with an even combination of discrete sampling of the initial mass function and high variability in the SFHs. This result demonstrates the importance of satisfying both the full-IMF and the constant-SFR assumptions for obtaining precise SFR estimates from FUV flux. Assuming a robust FUV extinction correction, we estimate that a factor of 2.5 uncertainty can be expected in FUV-based SFRs for regions smaller than 105 pc2 or a few hundred parsecs. We also examined ages and masses derived from UV flux under the common assumption that the regions are simple stellar populations (SSPs). The SFHs showed that most of the regions are not SSPs, and the age and mass estimates were correspondingly discrepant from the SFHs. For those regions with SSP-like SFHs, we found mean discrepancies of 10 Myr in age and a factor of 3–4 in mass. It was not possible to distinguish the SSP-like regions from the others based on integrated FUV flux.
Observational constraint on the dark energy scalar field

In this paper, we study three scalar fields, namely the quintessence, phantom, and tachyon fields, to explore the source of dark energy via the Gaussian processes method from the background and perturbation growth rate data. The corresponding reconstructions suggest that the dark energy should be dynamical. Moreover, the quintom field, which is a combination of the quintessence and phantom fields, is powerfully favored by the reconstruction. The mean values indicate that the potential in the quintessence field is a double exponential function, whereas in the phantom field is a double Gaussian function. This reconstruction can provide an important reference for the scalar field study. The two types of data employed reveal that the tachyon field is disadvantageous for describing the cosmic acceleration.
M2-Branes and Background Fields

We discuss the coupling of multiple M2-branes to the background 3-form and 6-form gauge fields of eleven-dimensional supergravity, including the coupling of the Fermions. In particular we show in detail how a natural generalization of the Myers flux-terms, along with the resulting curvature of the background metric, leads to mass terms in the effective field theory.