Miracle-dz/UniFAR-FTUs huggingface dataset:
Cross-calibrating X-ray detectors with clusters of galaxies: an IACHEC study

Aims. We used a sample of 11 nearby relaxed clusters of galaxies observed with the X-ray instruments XMM-Newton (EPIC) pn and MOS, Chandra ACIS-S and ACIS-I and BeppoSAX MECS to examine the cross-calibration of the energy dependence and normalisation of the effective area of these instruments as of December 2009. We also examined the Fe XXV/XXVI line ratio temperature measurement method for the pn and MOS. Methods. We performed X-ray spectral analysis on the XMM-Newton and Chandra data for a sample of 11 clusters. We obtained the information for BeppoSAX from DeGrandi & Molendi (2002). We compared the spectroscopic results obtained with different instruments for the same clusters in order to examine possible systematic calibration effects between the instruments. Results. We did not detect any significant systematic differences between the temperatures derived in the 2−7 keV band using the different instruments. Also, the EPIC temperatures derived from the bremsstrahlung continuum agreed with those obtained from the Fe XXV/XXVI emission line ratio, implying that the energy dependence of the hard band effective area of the above instruments is accurately calibrated. This also indicates that deviations from ionisation equilibrium and a Maxwellian electron velocity distribution are negligible in the regions studied in the cluster sample. We thus consider the IACHEC sample of clusters of galaxies as standard candles for the calibration of the energy dependence of the hard band (2− 7k eV) effective area of X-ray telescopes. On the other hand, the hard band EPIC/ACIS fluxes disagreed by 5−10% (i.e. at 6−25σ level) which indicates a similar level of uncertainty in the normalisations of the effective areas of these instruments in the 2−7 keV band. In the soft energy band (0.5−2.0 keV) there are greater cross-calibration differences between EPIC and ACIS. We found an energy-dependent increase of ACIS versus pn bias in the cross-calibration of the eff ective area by∼10% in the 0.5−2.0 keV band. This amounts to a systematic difference of (∼20%) in the temperatures measured by the ACIS and the EPIC-pn cameras in this band. Due to the high statistical weight of the soft band data, the 0.5−7.0 keV band temperature measurements of clusters of galaxies with EPIC/XMM-Newton or ACIS/Chandra are uncertain by ∼10−15% on average. These uncertainties will also affect the analysis of the wide band continuum spectra of other types of objects using ACIS or EPIC.
Magnetized effective QCD phase diagram

The QCD phase diagram in the temperature versus quark chemical potential plane is studied in the presence of a magnetic field, using the linear sigma model coupled to quarks. It is shown that the decrease of the couplings with increasing field strength obtained in this model leads to the critical temperature for the phase transition to decrease with increasing field intensity (inverse magnetic catalysis). This happens provided that plasma screening is properly accounted for. It is also found that with increasing field strength the location of the critical end point (CEP) in the phase diagram moves toward lower values of the critical quark chemical potential and larger values of the critical temperature. In addition, the CEP approaches the temperature axis for large values of the magnetic field. We argue that a similar behavior is to be expected in QCD, since the physical impact of the magnetic field, regardless of strength, is to produce a spatial dimension reduction, whereby virtual quark-antiquark pairs are closer on average and thus, the strength of their interaction decreases due to asymptotic freedom.
Multi-Objective Recommendation: Overview and Challenges

Recommender systems can be characterized as software solutions that provide users convenient access to relevant content. Traditionally, recommender systems research predominantly focuses on developing machine learning algorithms that aim to predict which content is relevant for individual users. In real-world applications, however, optimizing the accuracy of such relevance predictions as a single objective in many cases is not sufficient. Instead, multiple and often competing objectives have to be considered, leading to a need for more research in multi-objective recommender systems. We can differentiate between several types of such competing goals, including (i) competing recommendation quality objectives at the individual and aggregate level, (ii) competing objectives of different involved stakeholders, (iii) long-term vs. short-term objectives, (iv) objectives at the user interface level, and (v) system level objectives. In this paper we review these types of multi-objective recommendation settings and outline open challenges in this area.
Gravitational recoils of supermassive black holes in hydrodynamical simulations of gas-rich galaxies

We study the evolution of gravitationally recoiled supermassive black holes (BHs) in massive gas-rich galaxies by means of high-resolution hydrodynamical simulations. We find that the presence of a massive gaseous disc allows recoiled BHs to return to the centre on a much shorter time-scale than for purely stellar discs. Also, BH accretion and feedback can strongly modify the orbit of recoiled BHs and hence their return time-scale, besides affecting the distribution of gas and stars in the galactic centre. However, the dynamical interaction of kicked BHs with the surrounding medium is in general complex and can facilitate both a fast return to the centre as well as a significant delay. The Bondi-Hoyle-Lyttleton accretion rates of the recoiling BHs in our simulated galaxies are favourably high for the detection of off-centred active galactic nuclei (AGN) if kicked into gas-rich discs - up to a few per cent of the Eddington accretion rate - and are highly variable on time-scales of a few 10 7 yr. In major merger simulations of gas-rich galaxies, we find that gravitational recoils increase the scatter in the BH mass-host galaxy relationships compared to simulations without kicks, with the BH mass being more sensitive to recoil kicks than the bulge mass. The BH mass can be lowered by a factor of a few due to a recoil, even for a relatively short return time-scale, but the exact magnitude of the effect depends strongly on the BH binary hardening time-scale and on the efficiency of star formation in the central regions. A generic result of our numerical models is that the clumpy massive discs suggested by recent high-redshift observations, as well as the remnants of gas-rich mergers, exhibit a gravitational potential that falls steeply in the central regions, due to the dissipative concentration of baryons. As a result, supermassive BHs should only rarely be able to escape from massive galaxies at high redshifts, which is the epoch where the bulk of BH recoils is expected to occur.
How Neighborhood Exploration influences Novelty and Diversity in Graph Collaborative Filtering

Graph convolutional networks (GCNs) have recently been shown to improve the recommendation accuracy of collaborative filtering algorithms. Their message-passing schema refines user and item node representation by aggregating the informative content from the neighborhood. However, noisy contributions can flatten the differences among nodes after multiple hops, as not all user-item interactions are equally important. This impact is mitigated by (i) restricting the exploration depth in the graph and optionally weighting the neighbor contribution and (ii) going beyond the traditional message propagation at multiple hops. Nevertheless, it remains unclear how these exploration strategies affect the recommendation of novel and diverse products. This study investigates the influence of such GCN techniques on novelty and diversity of recommendations. It also assesses and motivates the impact of the number of exploration hops on the same metrics by analyzing interactions between same-type and different-type nodes, such as user-user and user-item. Code and datasets are available at: https://github.com/sisinflab/Novelty-Diversity-Graph.
THE DEEP2 GALAXY REDSHIFT SURVEY: DESIGN, OBSERVATIONS, DATA REDUCTION, AND REDSHIFTS

We describe the design and data analysis of the DEEP2 Galaxy Redshift Survey, the densest and largest high-precision redshift survey of galaxies at z ∼ 1 completed to date. The survey was designed to conduct a comprehensive census of massive galaxies, their properties, environments, and large-scale structure down to absolute magnitude MB = −20 at z ∼ 1 via ∼90 nights of observation on the Keck telescope. The survey covers an area of 2.8 deg2 divided into four separate fields observed to a limiting apparent magnitude of RAB = 24.1. Objects with z ≲ 0.7 are readily identifiable using BRI photometry and rejected in three of the four DEEP2 fields, allowing galaxies with z > 0.7 to be targeted ∼2.5 times more efficiently than in a purely magnitude-limited sample. Approximately 60% of eligible targets are chosen for spectroscopy, yielding nearly 53,000 spectra and more than 38,000 reliable redshift measurements. Most of the targets that fail to yield secure redshifts are blue objects that lie beyond z ∼ 1.45, where the [O ii] 3727 Å doublet lies in the infrared. The DEIMOS 1200 line mm−1 grating used for the survey delivers high spectral resolution (R ∼ 6000), accurate and secure redshifts, and unique internal kinematic information. Extensive ancillary data are available in the DEEP2 fields, particularly in the Extended Groth Strip, which has evolved into one of the richest multiwavelength regions on the sky. This paper is intended as a handbook for users of the DEEP2 Data Release 4, which includes all DEEP2 spectra and redshifts, as well as for the DEEP2 DEIMOS data reduction pipelines. Extensive details are provided on object selection, mask design, biases in target selection and redshift measurements, the spec2d two-dimensional data-reduction pipeline, the spec1d automated redshift pipeline, and the zspec visual redshift verification process, along with examples of instrumental signatures or other artifacts that in some cases remain after data reduction. Redshift errors and catastrophic failure rates are assessed through more than 2000 objects with duplicate observations. Sky subtraction is essentially photon-limited even under bright OH sky lines; we describe the strategies that permitted this, based on high image stability, accurate wavelength solutions, and powerful B-spline modeling methods. We also investigate the impact of targets that appear to be single objects in ground-based targeting imaging but prove to be composite in Hubble Space Telescope data; they constitute several percent of targets at z ∼ 1, approaching ∼5%–10% at z > 1.5. Summary data are given that demonstrate the superiority of DEEP2 over other deep high-precision redshift surveys at z ∼ 1 in terms of redshift accuracy, sample number density, and amount of spectral information. We also provide an overview of the scientific highlights of the DEEP2 survey thus far.
Protective Role of Podocytic IL-15 / STAT5 Pathway in Experimental Focal and Segmental Glomerulosclerosis

During glomerular diseases, podocyte-specific pathways can modulate the intensity of the lesions and prognosis. The therapeutic targeting of these pathways could thus improve the management and prognosis of chronic kidney diseases. The Janus Kinase/ Signal Transducer and Activator of Transcription (JAK/STAT) pathway, classically described in immune cells, has been recently described in intrinsic kidney cells. Here, we show, for the first time, that STAT5 is activated in human podocytes in focal segmental glomerulosclerosis (FSGS). Additionally, Stat5 podocyte-specific inactivation aggravates the functional and structural alterations in a mouse model of FSGS. This could be due, at least in part, to an inhibition of the autophagic flux. Finally, Interleukin 15 (IL-15), a classical activator of STAT5 in immune cells, increases STAT5 phosphorylation in human podocytes and its administration alleviates glomerular injury in vivo by maintaining the autophagy flux in podocytes. In conclusion, activating podocytic STAT5 with commercially available IL-15 represents a new therapeutic avenue with the potential for FSGS.
SUZAKU STUDIES OF THE CENTRAL ENGINE IN THE TYPICAL TYPE I SEYFERT NGC 3227: DETECTION OF MULTIPLE PRIMARY X-RAY CONTINUA WITH DISTINCT PROPERTIES

The type I Seyfert galaxy NGC 3227 was observed by Suzaku six times in 2008, with intervals of ∼1 week and net exposures of ∼50 ks each. Among the six observations, the source varied by nearly an order of magnitude; it was brightest in the first observation with a 2–10 keV luminosity of 1.2 × 1042 erg s−1, while faintest in the fourth observation with 2.9 × 1041 erg s−1. As it became fainter, the continuum in the 2–45 keV band became harder, while the narrow Fe-Kα emission line, detected on all occasions at 6.4 keV of the source rest frame, remained approximately constant in the photon flux. Through a method of variability-assisted broadband spectroscopy, the 2–45 keV spectrum of NGC 3227 was decomposed into three distinct components. One is a relatively soft power-law continuum with a photon index of ∼2.3, weakly absorbed and highly variable on timescales of ∼5 ks; it was observed only when the source was above a threshold luminosity of ∼6.6 × 1041 erg s−1 (in 2–10 keV), and was responsible for further source brightening beyond. Another is a harder and more absorbed continuum with a photon index of ∼1.6, which persisted through the six observations and varied slowly on timescales of a few weeks by a factor of ∼2. This component, carrying a major fraction of the broadband emission when the source is below the threshold luminosity, is considered as an additional primary emission. The last one is a reflection component with the narrow iron line, produced at large distances from the central black hole.
G protein-coupled receptor kinase-2 (GRK-2) controls exploration through neuropeptide signaling in Caenorhabditis elegans

Animals alter their behavior in manners that depend on environmental conditions as well as their developmental and metabolic states. For example, C. elegans is quiescent during larval molts or during conditions of satiety. By contrast, worms enter an exploration state when removed from food. Sensory perception influences movement quiescence (defined as a lack of body movement), as well as the expression of additional locomotor states in C. elegans that are associated with increased or reduced locomotion activity, such as roaming (exploration behavior) and dwelling (local search). Here we find that movement quiescence is enhanced, and exploration behavior is reduced in G protein-coupled receptor kinase grk-2 mutant animals. grk-2 was previously shown to act in chemosensation, locomotion, and egg-laying behaviors. Using neuron-specific rescuing experiments, we show that GRK-2 acts in multiple ciliated chemosensory neurons to control exploration behavior. grk-2 acts in opposite ways from the cGMP-dependent protein kinase gene egl-4 to control movement quiescence and exploration behavior. Analysis of mutants with defects in ciliated sensory neurons indicates that grk-2 and the cilium-structure mutants act in the same pathway to control exploration behavior. We find that GRK-2 controls exploration behavior in an opposite manner from the neuropeptide receptor NPR-1 and the neuropeptides FLP-1 and FLP-18. Finally, we show that secretion of the FLP-1 neuropeptide is negatively regulated by GRK-2 and that overexpression of FLP-1 reduces exploration behavior. These results define neurons and molecular pathways that modulate movement quiescence and exploration behavior. Author summary Many modulatory neurotransmitters affect behavior by binding to G protein-coupled receptors (GPCRs) and initiating signals that modify neuronal activity. GPCRs are regulated by G protein-coupled receptor kinases (GRKs). GRKs phosphorylate and promote the inactivation of GPCRs. Here we identify GRK-2 as a regulator of distinct locomotor states in C. elegans. We find that GRK-2 acts in olfactory sensory neurons to promote exploration and suppress movement quiescence. Additionally, we show that GRK-2 acts in opposition to a neuropeptide signaling pathway that acts in interneurons. Thus, this study demonstrates critical roles for GRK-2 in regulating neuromodulatory signaling and locomotor behavior.
Superstructures of Cubic and Hexagonal Diamonds Comprising a Family of Novel $sp^3$ Superhard Carbon Allotropes

Superstructures of cubic and hexagonal diamonds (h- and c-diamond) comprising a family of stable diamond-like $sp^3$ hybridized novel carbon allotropes are proposed, which are referred to as U$_n$-carbon where $n \geq 2$ denotes the number of structural layers in a unit cell. The conventional h- and c-diamond are included in this family as members with $n=2$ and 3, respectively. U$_n$-carbon ($n=4-6$), which are unveiled energetically and thermodynamically more stable than h-diamond and possess remarkable kinetic stabilities, are shown to be insulators with indirect gaps of $5.6 \sim 5.8$ eV, densities of $ 3.5 \sim 3.6$ g/cm$^3$, bulk modulus of $4.3 \sim 4.4 \times 10^{2}$ GPa, and Vickers hardness of $92.9 \sim 97.5$ GPa even harder than h- and c-diamond. The simulated x-ray diffraction and Raman spectra are presented for experimental characterization. These new structures of carbon would have a compelling impact in physics, chemistry, materials science and geophysics.
The (Un)Lonely Planet Guide: Formation and Evolution of Planetary Systems from a `Blue Dots' Perspective

In this contribution I summarize some recent successes, and focus on remaining challenges, in understanding the formation and evolution of planetary systems in the context of the Blue Dots initiative. Because our understanding is incomplete, we cannot yet articulate a "design reference mission" engineering matrix suitable for an exploration mission where success is defined as obtaining a spectrum of a potentially habitable world around a nearby star. However, as progress accelerates, we can identify observational programs that would address fundamental scientific questions through hypothesis testing such that the null result is interesting.
Quantum critical behavior in heavily doped LaFeAsO[1−x]Hx pnictide superconductors analyzed using nuclear magnetic resonance

We studied the quantum critical behavior of the second antiferromagnetic (AF) phase in the heavily electron-doped high-${T}_{c}$ pnictide, ${\mathrm{LaFeAsO}}_{1\ensuremath{-}x}{\mathrm{H}}_{x}$, by using a ${}^{75}\mathrm{As}$ and ${}^{1}\mathrm{H}$ nuclear magnetic resonance (NMR) technique. In the second AF phase, we observed a spatially modulated spin-density-wave-like state up to $x=0.6$ from the NMR spectral line shape and detected a low-energy excitation gap from the nuclear relaxation time ${T}_{1}$ of ${}^{75}\mathrm{As}$. The excitation gap closes at the AF quantum critical point (QCP) at $x\ensuremath{\approx}0.49$. The superconducting phase in a lower-doping regime contacts the second AF phase only at the AF QCP, and both phases are segregated from each other. The absence of AF critical fluctuations and the enhancement of the in-plane electric anisotropy are key factors for the development of superconductivity.
Reducing mitochondrial ribosomal gene expression does not alter metabolic health or lifespan in mice

Maintaining mitochondrial function is critical to an improved healthspan and lifespan. Introducing mild stress by inhibiting mitochondrial translation invokes the mitochondrial unfolded protein response (UPR^mt) and increases lifespan in several animal models. Notably, lower mitochondrial ribosomal protein (MRP) expression also correlates with increased lifespan in a reference population of mice. In this study, we tested whether partially reducing the gene expression of a critical MRP, Mrpl54 , reduced mitochondrial DNA-encoded protein content, induced the UPR^mt, and affected lifespan or metabolic health using germline heterozygous Mrpl54 mice. Despite reduced Mrpl54 expression in multiple organs and a reduction in mitochondrial-encoded protein expression in myoblasts, we identified few significant differences between male or female Mrpl54 ^+/− and wild type mice in initial body composition, respiratory parameters, energy intake and expenditure, or ambulatory motion. We also observed no differences in glucose or insulin tolerance, treadmill endurance, cold tolerance, heart rate, or blood pressure. There were no differences in median life expectancy or maximum lifespan. Overall, we demonstrate that genetic manipulation of Mrpl54 expression reduces mitochondrial-encoded protein content but is not sufficient to improve healthspan in otherwise healthy and unstressed mice.
Reasoning Visual Dialogs With Structural and Partial Observations

We propose a novel model to address the task of Visual Dialog which exhibits complex dialog structures. To obtain a reasonable answer based on the current question and the dialog history, the underlying semantic dependencies between dialog entities are essential. In this paper, we explicitly formalize this task as inference in a graphical model with partially observed nodes and unknown graph structures (relations in dialog). The given dialog entities are viewed as the observed nodes. The answer to a given question is represented by a node with missing value. We first introduce an Expectation Maximization algorithm to infer both the underlying dialog structures and the missing node values (desired answers). Based on this, we proceed to propose a differentiable graph neural network (GNN) solution that approximates this process. Experiment results on the VisDial and VisDial-Q datasets show that our model outperforms comparative methods. It is also observed that our method can infer the underlying dialog structure for better dialog reasoning.
Deep unfolded convolutional dictionary learning for motif discovery

We present a principled representation learning approach based on convolutional dictionary learning (CDL) for motif discovery. We unroll an iterative algorithm that optimizes CDL as a forward pass in a neural network, resulting in a network that is fully interpretable, fast, and capable of finding motifs in large datasets. Simulated data show that our network is more sensitive and specific for discovering binding sites that exhibit complex binding patterns than popular motif discovery methods such as STREME and HOMER. Our network reveals statistically significant motifs and their diverse binding modes from the JASPAR database that are currently not reported.