Miracle-dz/UniFAR-FTUs huggingface dataset:
Geometries of edge and mixed dislocations in bcc Fe from first-principles calculations

We use DFT to compute core structures of $a_0[100](010)$ edge, $a_0[100](011)$ edge, $a_0/2[\bar{1}\bar{1}1](1\bar{1}0)$ edge, and $a_0/2[111](1\bar{1}0)$ $71^{\circ}$ mixed dislocations in bcc Fe. The calculations use flexible boundary conditions (FBC), which allow dislocations to relax as isolated defects by coupling the core to an infinite harmonic lattice through the lattice Green function (LGF). We use LGFs of dislocated geometries in contrast to previous FBC-based dislocation calculations that use the bulk crystal LGF. Dislocation LGFs account for changes in topology in the core as well as strain throughout the lattice. A bulk-like approximation for the force constants in a dislocated geometry leads to LGFs that optimize the cores of the $a_0[100](010)$ edge, $a_0[100](011)$ edge, and $a_0/2[111](1\bar{1}0)$ $71^{\circ}$ mixed dislocations. This approximation fails for the $a_0/2[\bar{1}\bar{1}1](1\bar{1}0)$ dislocation, so here we derive the LGF using accurate force constants from a Gaussian approximation potential. The standard deviations of dislocation Nye tensor distributions quantify the widths of the cores. The relaxed cores are compact, and the magnetic moments on the Fe atoms closely follow the volumetric strain distributions in the cores. We also compute the core structures of these dislocations using eight different classical interatomic potentials, and quantify symmetry differences between the cores using the Fourier coefficients of their Nye tensor distributions. Most of the core structures computed using the classical potentials agree well with DFT results. The DFT geometries provide benchmarking for classical potential studies of work-hardening, as well as substitutional and interstitial sites for computing solute-dislocation interactions that serve as inputs for mesoscale models of solute strengthening and solute diffusion near dislocations.
Weighing the Giants - I. Weak-lensing masses for 51 massive galaxy clusters: project overview, data analysis methods and cluster images

This is the first in a series of papers in which we measure accurate weak-lensing masses for 51 of the most X-ray luminous galaxy clusters known at redshifts 0:15 . zCl . 0:7, in order to calibrate X-ray and other mass proxies for cosmological cluster experiments. The primary aim is to improve the absolute mass calibration of cluster observables, currently the dominant systematic uncertainty for cluster count experiments. Key elements of this work are the rigorous quantification of systematic uncertainties, high quality data reduction and photometric calibration, and the “blind” nature of the analysis to avoid confirmation bias. Our target clusters are drawn from X-ray catalogs based on the ROSAT All-Sky Survey, and provide a versatile calibration sample for many aspects of cluster cosmology. We have acquired widefield, high-quality imaging using the Subaru and CFHT telescopes for all 51 clusters, in at least three bands per cluster. For a subset of 27 clusters, we have data in at least five bands, allowing accurate photometric redshift estimates of lensed galaxies. In this paper, we describe the cluster sample and observations, and detail the processing of the SuprimeCam data to yield high-quality images suitable for robust weak-lensing shape measurements and precision photometry. For each cluster, we present wide-field three-color optical images and maps of the weak-lensing mass distribution, the optical light distribution, and the X-ray emission. These provide insights into the large-scale structure in which the clusters are embedded. We measure the o sets between X-ray flux centroids and the Brightest Cluster Galaxies in the clusters, finding these to be small in general, with a median of 20 kpc. For o sets . 100 kpc, weak-lensing mass measurements centered on the Brightest Cluster Galaxies agree well with values determined relative to the X-ray centroids; miscentering is therefore not a significant source of systematic uncertainty for our weak-lensing mass measurements. In accompanying papers we discuss the key aspects of our photometric calibration and photometric redshift measurements (Kelly et al.), and measure cluster masses using two methods, including a novel Bayesian weak-lensing approach that makes full use of the photometric redshift probability distributions for individual background galaxies (Applegate et al.). In subsequent papers, we will incorporate these weak-lensing mass measurements into a self-consistent framework to simultaneously determine cluster scaling relations and cosmological parameters.
Protostellar accretion traced with chemistry: Comparing synthetic C18O maps of embedded protostars to real observations

Context: Understanding how protostars accrete their mass is a central question of star formation. One aspect of this is trying to understand whether the time evolution of accretion rates in deeply embedded objects is best characterised by a smooth decline from early to late stages or by intermittent bursts of high accretion. Aims: We create synthetic observations of deeply embedded protostars in a large numerical simulation of a molecular cloud, which are compared directly to real observations. The goal is to compare episodic accretion events in the simulation to observations and to test the methodology used for analysing the observations. Methods: Simple freeze-out and sublimation chemistry is added to the simulation, and synthetic C$^{18}$O line cubes are created for a large number of simulated protostars. The spatial extent of C$^{18}$O is measured for the simulated protostars and compared directly to a sample of 16 deeply embedded protostars observed with the Submillimeter Array. If CO is distributed over a larger area than predicted based on the protostellar luminosity, it may indicate that the luminosity has been higher in the past and that CO is still in the process of refreezing. Results: Approximately 1% of the protostars in the simulation show extended C$^{18}$O emission, as opposed to approximately 50% in the observations, indicating that the magnitude and frequency of episodic accretion events in the simulation is too low relative to observations. The protostellar accretion rates in the simulation are primarily modulated by infall from the larger scales of the molecular cloud, and do not include any disk physics. The discrepancy between simulation and observations is taken as support for the necessity of disks, even in deeply embedded objects, to produce episodic accretion events of sufficient frequency and amplitude.
Fermi/GBM Short Gamma-ray Burst Catalog and Case Study for GRB 170817A/GW 170817

Motivating by the discovery of association between GW 170817 and sGRB 170817A, we present a comprehensive analysis for sGRBs observed with Fermi/GBM in 9 operation years and study the properties of sGRB 170817A -like events. We derive a catalog of 275 typical sGRBs and 48 sGRB 170817A-like weak events from the GBM data of 2217 GRBs. We visibly identify two patterns of their light curve, single episode (Pattern I, 61\% of the SGRBs) and multiple episodes (Pattern II, 39\% of the SGRBs). Their duration distribution shows a tentative bimodal feature. Their spectra can be fitted with a cutoff power-law model, except for 4 sGRBs, and the spectral indices normally distribute at $\Gamma=0.69\pm 0.40$. Their $E_p$ values show a tentative bimodal distribution with peaks at 145 keV and 500 keV. No correlation among $T_{90}$, $E_p$, and $\Gamma$ is found. GRB 170817A is a soft, weak sGRB with $ E_{p}=124\pm 106$ keV, $L_{\rm iso}=(5.67\pm4.65)\times10^{46}\rm ~erg~s^{-1}$, and $E_{\rm iso}=(3.23\pm2.65)\times10^{46}\rm ~erg$. It follows the $E_{\rm iso}-E_{\rm p}$ relation of typical short GRBs. Its lightcurve is of Pattern II. Two lightcurve patterns, together with the potential two components in the $E_{\rm p}$ and $T_{90}$ distributions, we suspect that the current sample may include two distinct types of sGRBs from different progenitors. sGRB 170817A-like events may be from NS-NS mergers and those sGRBs with a Pattern I lightcurve may be from another distinct type of compact binary.
Simulations of the polarized radio sky and predictions on the confusion limit in polarization for future radio surveys

Numerical simulations offer the unique possibility to forecast the results of surveys and targeted observations that will be performed with next generation instruments like the Square Kilometre Array. In this paper, we investigate for the first time how future radio surveys in polarization will be affected by confusion noise. To do this, we produce 1.4 GHz simulated full-Stokes images of the extra-galactic sky by modelling various discrete radio sources populations. The results of our modelling are compared to data in the literature to check the reliability of our procedure. We also estimate the number of polarized sources detectable by future surveys. Finally, from the simulated images we evaluate the confusion limits in I, Q, and U Stokes parameters, giving analytical formulas of their behaviour as a function of the angular resolution.
A Logistic Regression Model for Biomechanical Risk Classification in Lifting Tasks

Lifting is one of the most potentially harmful activities for work-related musculoskeletal disorders (WMSDs), due to exposure to biomechanical risk. Risk assessment for work activities that involve lifting loads can be performed through the NIOSH (National Institute of Occupational Safety and Health) method, and specifically the Revised NIOSH Lifting Equation (RNLE). Aim of this work is to explore the feasibility of a logistic regression model fed with time and frequency domains features extracted from signals acquired through one inertial measurement unit (IMU) to classify risk classes associated with lifting activities according to the RNLE. Furthermore, an attempt was made to evaluate which are the most discriminating features relating to the risk classes, and to understand which inertial signals and which axis were the most representative. In a simplified scenario, where only two RNLE variables were altered during lifting tasks performed by 14 healthy adults, inertial signals (linear acceleration and angular velocity) acquired using one IMU placed on the subject’s sternum during repeated rhythmic lifting tasks were automatically segmented to extract several features in the time and frequency domains. The logistic regression model fed with significant features showed good results to discriminate “risk” and “no risk” NIOSH classes with an accuracy, sensitivity and specificity equal to 82.8%, 84.8% and 80.9%, respectively. This preliminary work indicated that a logistic regression model—fed with specific inertial features extracted by signals acquired using a single IMU sensor placed on the sternum—is able to discriminate risk classes according to the RNLE in a simplified context, and therefore could be a valid tool to assess the biomechanical risk in an automatic way also in more complex conditions (e.g., real working scenarios).
Is there more than meets the eye? Presence and role of sub-micron grains in debris discs

Context. The presence of sub-micron grains has been inferred in several debris discs, usually because of a blue colour of the spectrum in scattered light or a pronounced silicate band around 10 μm, even though these particles should be blown out by stellar radiation pressure on very short timescales. So far, no fully satisfying explanation has been found for this apparent paradox. Aims. We investigate the possibility that the observed abundances of sub-micron grains could be naturally produced in bright debris discs, where the high collisional activity produces them at a rate high enough to partially compensate for their rapid removal. We also investigate to what extent this potential presence of small grains can affect our understanding of some debris disc characteristics. Methods. We used a numerical collisional code to follow the collisional evolution of a debris disc down to sub-micron grains far below the limiting blow-out size sblow. We considered compact astrosilicates and explored different configurations: A and G stars, cold and warm discs, bright and very bright systems. We then produced synthetic spectra and spectral energy distributions, where we identified and quantified the signature of unbound sub-micron grains. Results. We find that in bright discs (fractional luminosity ≳10−3) around A stars, the number of sub-micron grains is always high enough to leave detectable signatures in scattered light where the disc colour becomes blue, and also in the mid-IR (10 ≲ λ ≲ 20 μm), where they boost the disc luminosity by at least a factor of 2 and induce a pronounced silicate solid-state band around 10 μm. We also show that with this additional contribution of sub-micron grains, the spectral energy distribution can mimic that of two debris belts separated by a factor of ~2 in radial distance. For G stars, the effect of s ≤ sblow grains remains limited in the spectra although they dominate the geometrical cross section of the system. We also find that for all considered cases, the halo of small (bound and unbound) grains that extends far beyond the main disc contributes to ~50% of the flux up to λ ~ 50 μm wavelengths.
Gut Microbiota and Tumor Immune Escape: A New Perspective for Improving Tumor Immunotherapy

Simple Summary The gut microbiota is a commensal microbiota living in the human intestine. Its status and composition have a profound impact on human antitumor immunity. Gut microbiota and its metabolites can influence tumor immune escape through immune cells and inflammatory factors, changing the patient’s response to immunotherapy. Protecting normal gut microbiota or optimizing its composition can improve the effects of tumor immunotherapy and bring new hope for cancer treatment. Abstract The gut microbiota is a large symbiotic community of anaerobic and facultative aerobic bacteria inhabiting the human intestinal tract, and its activities significantly affect human health. Increasing evidence has suggested that the gut microbiome plays an important role in tumor-related immune regulation. In the tumor microenvironment (TME), the gut microbiome and its metabolites affect the differentiation and function of immune cells regulating the immune evasion of tumors. The gut microbiome can indirectly influence individual responses to various classical tumor immunotherapies, including immune checkpoint inhibitor therapy and adoptive immunotherapy. Microbial regulation through antibiotics, prebiotics, and fecal microbiota transplantation (FMT) optimize the composition of the gut microbiome, improving the efficacy of immunotherapy and bringing a new perspective and hope for tumor treatment.
Interaction between molecular clouds and MeV–TeV cosmic-ray protons escaped from supernova remnants

Recent discovery of the X-ray neutral iron line (Fe i Kα at 6.40 keV) around several supernova remnants (SNRs) show that MeV cosmic-ray (CR) protons are distributed around the SNRs and are interacting with neutral gas there. We propose that these MeV CRs are the ones that have been accelerated at the SNRs together with GeV–TeV CRs. In our analytical model, the MeV CRs are still confined in the SNR when the SNR collides with molecular clouds. After the collision, the MeV CRs leak into the clouds and produce the neutral iron line emissions. On the other hand, GeV–TeV CRs had already escaped from the SNRs and emitted gamma-rays through interaction with molecular clouds surrounding the SNRs. We apply this model to the SNRs W 28 and W 44 and show that it can reproduce the observations of the iron line intensities and the gamma-ray spectra. This could be additional support of the hadronic scenario for the gamma-ray emissions from these SNRs.
Strategies for the Modelisation of Electric Vehicle Energy Consumption: A Review

The continuous technical improvements involving electric motors, battery packs, and general powertrain equipment make it strictly necessary to predict or evaluate the energy consumption of electric vehicles (EVs) with reasonable accuracy. The significant improvements in computing power in the last decades have allowed the implementation of various simulation scenarios and the development of strategies for vehicle modelling, thus estimating energy consumption with higher accuracy. This paper gives a general overview of the strategies adopted to model EVs for evaluating or predicting energy consumption. The need to develop such solutions is due to the basis of each analysis, as well as the type of results that must be produced and delivered. This last point strongly influences the whole set-up process of the analysis, from the available and collected dataset to the choice of the algorithm itself.
VITAMIN D3 AS A HORMONE - THE ROLE IN THE DEVELOPMENT OF ATHEROSCLEROSIS

Vitamin D3 deficiency is common worldwide (Holick, 2006) (1). For example, vitamin D3 deficiency was 77% in the US population (Ginde et al., 2009) (2). According to our data, vitamin D3 deficiency was found in 80% of CHD patients (3). Ecological studies have shown a higher incidence of cardiovascular disease with increasing distance from the equator, suggesting an association with vitamin D insufficiency in regions with less sun exposure (4). Low 25(OH)D concentrations may increase the risk of hypertension, peripheral vascular disease, diabetes, obesity, myocardial infarction, heart failure, and cardiac mortality (4,5,6,7), low 25(OH)D levels are associated with endothelial dysfunction, inflammation, increased vascular stiffness and arterial calcification (8).
Efficient cold outflows driven by cosmic rays in high redshift galaxies and their global effects on the IGM

We present semi-analytical models of galactic outflows in high redshift galaxies driven by both hot thermal gas and non-thermal cosmic rays. Thermal pressure alone may not sustain a large scale outflow in low mass galaxies (i.e $M\sim 10^8$~M$_\odot$), in the presence of supernovae (SNe) feedback with large mass loading. We show that inclusion of cosmic ray pressure allows outflow solutions even in these galaxies. In massive galaxies for the same energy efficiency, cosmic ray driven winds can propagate to larger distances compared to pure thermally driven winds. On an average gas in the cosmic ray driven winds has a lower temperature which could aid detecting it through absorption lines in the spectra of background sources. Using our constrained semi-analytical models of galaxy formation (that explains the observed UV luminosity functions of galaxies) we study the influence of cosmic ray driven winds on the properties of the intergalactic medium (IGM) at different redshifts. In particular, we study the volume filling factor, average metallicity, cosmic ray and magnetic field energy densities for models invoking atomic cooled and molecular cooled halos. We show that the cosmic rays in the IGM could have enough energy that can be transferred to the thermal gas in presence of magnetic fields to influence the thermal history of the intergalactic medium. The significant volume filling and resulting strength of IGM magnetic fields can also account for recent $\gamma$-ray observations of blazars.
Polycrystalline Crusts in Accreting Neutron Stars

The crust of accreting neutron stars plays a central role in many different observational phenomena. In these stars, heavy elements produced by H–He burning in the rapid proton capture (rp-) process continually freeze to form new crust. In this paper, we explore the expected composition of the solid phase. We first demonstrate using molecular dynamics that two distinct types of chemical separations occur, depending on the composition of the rp-process ashes. We then calculate phase diagrams for three-component mixtures and use them to determine the allowed crust compositions. We show that, for the large range of atomic numbers produced in the rp-process (Z ∼ 10–50), the solid that forms has only a small number of available compositions. We conclude that accreting neutron star crusts should be polycrystalline, with domains of distinct composition. Our results motivate further work on the size of the compositional domains and have implications for crust physics and accreting neutron star phenomenology.
Evidence of Interacting Elongated Filaments in the Star-forming Site AFGL 5142

To probe the ongoing physical mechanism, we studied a wide-scale environment around AFGL 5142 (area ∼25 pc × 20 pc) using a multiwavelength approach. The Herschel column density (N(H2)) map reveals a massive inverted Y-like structure (mass ∼6280 M⊙), which hosts a pair of elongated filaments (lengths >10 pc). The Herschel temperature map depicts the filaments in a temperature range of ∼12.5–13.5 K. These elongated filaments overlap each other at several places, where N(H2) > 4.5 × 1021 cm−2. The 12CO and 13CO line data also show two elongated cloud components (around −1.5 and −4.5 km s−1) toward the inverted Y-like structure, which are connected in the velocity space. First moment maps of CO confirm the presence of two intertwined filamentary clouds along the line of sight. These results explain the morphology of the inverted Y-like structure through a combination of two different filamentary clouds, which are also supported by the distribution of the cold H i gas. Based on the distribution of young stellar objects (YSOs), star formation (SF) activities are investigated toward the inverted Y-like structure. The northern end of the structure hosts AFGL 5142 and tracers of massive SF, where high surface density of YSOs (i.e., 5–240 YSOs pc−2) reveals strong SF activity. Furthermore, noticeable YSOs are found toward the overlapping zones of the clouds. All this observational evidence supports a scenario of collision/interaction of two elongated filamentary clouds/flows, which appears to explain SF history in the site AFGL 5142.
Fuchsian analysis of S2 × S1 and S3 Gowdy spacetimes

The Gowdy spacetimes are vacuum solutions of the Einstein equations with two commuting Killing vectors having compact spacelike orbits with T3, S2 × S1 or S3 topology. In the case of T3 topology, Kichenassamy and Rendall have found a family of singular solutions which are asymptotically velocity dominated by construction. In the case when the velocity is between 0 and 1, the solutions depend on the maximal number of free functions. We consider the similar case with S2 × S1 or S3 topology, where the main complication is the presence of symmetry axes. The results for T3 may be applied locally except at the axes, where one of the Killing vectors degenerates. We use Fuchsian techniques to show the existence of singular solutions similar to the T3 case. We first solve the analytic case and then generalize to the smooth case by approximating smooth data with a sequence of analytic data. However, for the metric to be smooth at the axes, the velocity must be −1 or 3 there, which is outside the range where the constructed solutions depend on the full number of free functions. A plausible explanation is that in general a spiky feature may develop at the axis, a situation which is unsuitable for a direct treatment by Fuchsian methods.
Quintessence, cosmic coincidence, and the cosmological constant

Recent observations suggest that a large fraction of the energy density of the Universe has negative pressure. One explanation is vacuum energy density; another is quintessence in the form of a scalar field slowly evolving down a potential. In either case, a key problem is to explain why the energy density nearly coincides with the matter density today. The densities decrease at different rates as the Universe expands, so coincidence today appears to require that their ratio be set to a specific, infinitesimal value in the early Universe. In this paper, we introduce the notion of a {open_quotes}tracker field,{close_quotes} a form of quintessence, and show how it may explain the coincidence, adding new motivation for the quintessence scenario. {copyright} {ital 1999} {ital The American Physical Society}