Miracle-dz/UniFAR-FTUs huggingface dataset:
The kinematic signature of the inspiral phase of massive binary black holes

Supermassive black holes are expected to pair as a result of galaxy mergers, and form a bound binary at parsec or sub-parsec scales. These scales are unresolved even in nearby galaxies, and thus detection of non-active black hole binaries must rely on stellar dynamics. Here we show that these systems could be indirectly detected through the trail that the black holes leave as they spiral inwards. We analyze two numerical simulations of inspiralling black holes (equal masses and 10:1 mass ratio) in the stellar environment of a galactic centre. We studied the effect of the binary on the structure of the stellar population, with particular emphasis on projected kinematics and directly measurable moments of the velocity distribution. We present those moments as high-resolution 2D maps. As shown in past scattering experiments, a torus of stars counter-rotating with respect to the black holes exists in scales ~ 5 to 10 times larger than the binary separation. While this is seen in the average velocity map in the unequal mass case, it is obscured by a more strongly co-rotating outer region in the equal mass case; however, the inner counter-rotation could still be detected by studying the higher moments of the velocity distribution. Additionally, the maps reveal a dip in velocity dispersion in the inner region, as well as more pronounced signatures in the higher distribution moments. These maps could serve as templates for integral field spectroscopy observations of nearby galactic centres. The discovery of such signatures may help census the population of supermassive black hole binaries and refine signal rate predictions for future space-based low frequency gravitational wave detectors.
Modelling the recurrent nova U Scorpii in quiescence

VLT and SALT spectroscopy of U Sco were obtained $\sim$18 and $\sim$30 months after the 2010 outburst. From these spectra the accretion disc is shown to take at least 18 months to become fully reformed. The spectral class of the companion is constrained to be F8$^{+5}_{-6}$\,IV-V at the 95% confidence level when the irradiated face of the companion is visible.
The Mid-Infrared Emission of Seyfert Galaxies: A New Analysis of ISOCAM Data

We present mid-infrared data of a sample of 57 AGNs obtained with the instrument ISOCAM on board the Infrared Space Observatory (ISO) satellite. The images were obtained through the LW2 (6.75 μm) and LW7 (9.62 μm) filters. This is a new analysis of the Clavel et al. galaxy sample, which is divided into 26 type 1 (≤1.5) and 28 type 2 (>1.5) Seyfert galaxies, plus three QSOs. The spatial resolution of the images allows us to separate the nuclear and the extended contributions to the total emission after decomposing the brightness profiles into different morphological components. The most common components are a central point source (identified as the active nucleus) and an exponential disk. In some cases a bulge, a bar, or a ring are needed. The relative contribution of the nucleus to the total emission appears larger in Seyfert 1 than in Seyfert 2 types. This result confirms that both types of Seyfert galaxies are different in the mid-infrared wavelength range and supports the existence of a structure which produces anisotropic emission in this wavelength range. We have also explored correlations between the mid-infrared and the radio and X-ray wavelength ranges. The well-established radio/infrared correlation is maintained in our sample for the global emission of the galaxies. If only the nuclear infrared emission is considered, then a nonlinear correlation is apparent in the luminosity-luminosity scatter diagram. The ratio between the intrinsic hard X-ray and the nuclear mid-infrared emission presents large scatter and slightly larger values for type 2 Seyfert galaxies. These results seem to be consistent with the presence of a clumpy dusty torus surrounding the active nucleus.
Uncovering the Cognitive, Psychological, and Social Mechanisms Affecting TikTok’s Reuse Intention: Verifying the Role of Platform Characteristics, Psychological Distance, and Social Identity

With the consumption of user generated online contents content increasing rapidly, the short clip market in China is fast growing. TikTok, a leading short clip platform, has achieved great business success. However, there is not much research done on TikTok platform from the current customers’ social and psychological viewpoints. Against this background, this study aims to verify the cognitive, emotional and behavioral pre-cursors of platform reuse decision by focusing on the platform’s informational contents, users’ network traits, user attachment, user engagement, psychological distance, and social identity. This way, this study extends the current understanding on the antecedent factors affecting users’ behavioral intention of TikTok through broader perspectives including social and psychological predictors. During October 2021, an online questionnaire survey was administered in China. On the subject of TikTok platform. Firstly, the study found that both information characteristics and social network traits significantly affect the user engagement as well as attachment. Secondly, both the user attachment and engagement have a significant impact on reuse intention. Thirdly, the psychological distance plays a significant moderating role in the relationship between bridging network and attachment. Finally, the social identity significantly moderates the relationship between bridging network and user engagement. The study result is expected to add to the current literature which has not examined the antecedent factors affecting users’ reuse intention of TikTok from broader aspects including social and psychological variables.
Obscured flat spectrum radio active galactic nuclei as sources of high-energy neutrinos

Active galactic nuclei (AGN) are believed to be one of the main source candidates for the high-energy (TeV-PeV) cosmic neutrino flux recently discovered by the IceCube neutrino observatory. Nevertheless, several correlation studies between AGN and the cosmic neutrinos detected by IceCube show no significance. Therefore, in this article we consider a specific subclass of AGN for which an increased neutrino production is expected. This subclass contains AGN for which their high-energy jet is pointing toward Earth. Furthermore, we impose the condition that the jet is obscured by gas or dust surrounding the AGN. A method is presented to determine the total column density of the obscuring medium, which is probed by determining the relative x-ray attenuation with respect to the radio flux as obtained from the AGN spectrum. The total column density allows us to probe the interaction of the jet with the surrounding matter, which leads to additional neutrino production. Finally, starting from two different source catalogs, this method is applied to specify a sample of low redshift radio galaxies for which an increased neutrino production is expected.
Physical and radiative properties of the first-core accretion shock

Context. Radiative shocks play a dominant role in star formation. The accretion shocks on first and second Larson cores involve radiative processes and are thus characteristic of radiative shocks. Aims. In this study, we explore the formation of the first Larson core and characterize the radiative and dynamical properties of the accretion shock, using both analytical and numerical approaches. Methods. We developed both numerical radiation-hydrodynamics calculations and a semi-analytical model that characterize radiative shocks in various physical conditions, for radiating or barotropic fluids. Then, we performed 1D spherical collapse calculations of the first Larson core, using a grey approximation for the opacity of the material. We considered three different models for radiative transfer: the barotropic approximation, the flux limited diffusion approximation, and the more complete M1 model. We investigate the characteristic properties of the collapse and of the first core formation. Comparison between the numerical results and our semianalytical model for radiative shocks shows that the latter reproduces the core properties obtained with the numerical calculations quite well. Results. The accretion shock on the first Larson core is found to be supercritical; i.e., the post and pre-shock temperatures are equal, implying that all the accretion shock energy on the core is radiated away. The shock properties are described well by the semianalytical model. The flux-limited diffusion approximation is found to agree quite well with the results based on the M1 model of radiative transfer, and is thus appropriate for studying the star formation process and allows a tractable and relatively correct treatment of radiative transfer in multidimensional radiation-hydrodynamics calculations. In contrast, the barotropic approximation does not correctly describe the thermal properties of the gas during the collapse.
THE REDSHIFT DISTRIBUTION OF INTERVENING WEAK Mg ii QUASAR ABSORBERS AND A CURIOUS DEPENDENCE ON QUASAR LUMINOSITY

We have identified 469 Mg ii λλ2796, 2803 doublet systems having Wr ⩾ 0.02 Å in 252 Keck/High Resolution Echelle Spectrometer and UVES/Very Large Telescope quasar spectra over the redshift range 0.1 < z < 2.6. Using the largest sample yet of 188 weak Mg ii systems (0.02 Å ⩽Wr < 0.3 Å), we calculate their absorber redshift path density, dN/dz. We find clear evidence of evolution, with dN/dz peaking at z ∼ 1.2, and that the product of the absorber number density and cross section decreases linearly with increasing redshift; weak Mg ii absorbers seem to vanish above z ≃ 2.7. If the absorbers are ionized by the UV background, we estimate number densities of 106–109 Mpc−3 for spherical geometries and 102–105 Mpc−3 for more sheetlike geometries. We also find that dN/dz toward intrinsically faint versus bright quasars differs significantly for weak and strong (Wr ⩾ 1.0 Å) absorbers. For weak absorption, dN/dz toward bright quasars is ∼25% higher than toward faint quasars (10σ at low redshift, 0.4 ⩽ z ⩽ 1.4, and 4σ at high redshift, 1.4 < z ⩽ 2.34). For strong absorption the trend reverses, with dN/dz toward faint quasars being ∼20% higher than toward bright quasars (also 10σ at low redshift and 4σ at high redshift). We explore scenarios in which beam size is proportional to quasar luminosity and varies with absorber and quasar redshifts. These do not explain dN/dz's dependence on quasar luminosity.
Locally-Active Memristors-Based Reactance-Less Oscillator

Locally-active memristors (LAMs) have broad application prospects in neuromorphic computing due to their nanoscale, low-power consumption, and local activity. A LAM combined with a DC bias and a reactance element (capacitor or inductor) can form an oscillator. Since the LAM exhibits capacitive or inductive impedance characteristic at the specific operating points, it can replace the reactance element and further implement a reactance-less oscillator. Two different LAMs-based reactance-less oscillators are proposed. One is based on two voltage-controlled (VC) LAMs, and the other mainly contains two current-controlled (CC) LAMs. Local activity theory, Hopf bifurcation theory, and the small-signal analysis method are used to quantitatively deduce the oscillation condition of the proposed circuit. A simple VC LAM mathematical model is taken as an example to conduct the analysis and verification. Both simulation and experiment results confirm the feasibility and practicability of the proposed LAMs-based reactance-less oscillator.
Non-Gaussianity from curvatons revisited

We investigate density perturbations sourced by a curvaton with a generic energy potential. The key feature of a curvaton potential which deviates from a quadratic is that the curvaton experiences a non-uniform onset of its oscillation. This sources additional contributions to the resulting density perturbations, and we especially find that the non-Gaussianity parameter f_NL can become large with either sign no matter whether the curvaton dominates or subdominates the universe when it decays. Such non-quadratic curvaton potentials are required in order to produce a red-tilted density perturbation spectrum (without invoking large-field inflation), and are also motivated by explicit curvaton models based on microscopic physics. We further apply our generic results to the case where the curvaton is a pseudo-Nambu-Goldstone (NG) boson of a broken U(1) symmetry, and show that the resulting density perturbations are strongly enhanced towards the hilltop region of the energy potential, accompanied by a mild increase of the non-Gaussianity. Such hilltop NG curvatons can produce observationally suggested density perturbations under wide ranges of inflation/reheating scales, and further predict the non-Gaussianity of the density perturbations to lie within the range 10 <~ f_NL <~ 30.
Meta Reinforcement Learning for Optimal Design of Legged Robots

The process of robot design is a complex task and the majority of design decisions are still based on human intuition or tedious manual tuning. A more informed way of facing this task is computational design methods where design parameters are concurrently optimized with corresponding controllers. Existing approaches, however, are strongly influenced by predefined control rules or motion templates and cannot provide end-to-end solutions. In this paper, we present a design optimization framework using model-free meta reinforcement learning, and its application to the optimizing kinematics and actuator parameters of quadrupedal robots. We use meta reinforcement learning to train a locomotion policy that can quickly adapt to different designs. This policy is used to evaluate each design instance during the design optimization. We demonstrate that the policy can control robots of different designs to track random velocity commands over various rough terrains. With controlled experiments, we show that the meta policy achieves close-to-optimal performance for each design instance after adaptation. Lastly, we compare our results against a model-based baseline and show that our approach allows higher performance while not being constrained by predefined motions or gait patterns.
COVID-19 and the Human Gut Microbiome: An Under-Recognized Association

Coronavirus disease 2019 (COVID-19) is an infectious disease with a wide range of respiratory and extrapulmonary symptoms, as well as gastrointestinal symptoms. Despite recent research linking gut microbiota to infectious diseases like influenza, minimal information is known about the gut microbiota’s function in COVID-19 pathogenesis. Studies suggest that dysbiosis of the gut microbiota and gut barrier dysfunction may play a role in COVID-19 pathogenesis by disrupting host immune homeostasis. Regardless of whether patients had taken medication or disease severity, the gut microbiota composition was significantly altered in COVID-19 patients compared to non-COVID-19 individuals. Several gut commensals with recognized immunomodulatory potential, such as Faecalibacterium prausnitzii, Eubacterium rectale, and bifidobacteria, were underrepresented in patients and remained low in samples taken several weeks after disease resolution. Furthermore, even with disease resolution, dysbiosis in the gut microbiota may contribute to chronic symptoms, underscoring the need to learn more about how gut microbes play a role in inflammation and COVID-19.
Exponential spectra in $L^2(\mu)$

Let $\mu$ be a Borel probability measure with compact support. We consider exponential type orthonormal bases, Riesz bases and frames in $L^2(\mu)$. We show that if $L^2(\mu)$ admits an exponential frame, then $\mu$ must be of pure type. We also classify various $\mu$ that admits either kind of exponential bases, in particular, the discrete measures and their connection with integer tiles. By using this and convolution, we construct a class of singularly continuous measures that has an exponential Riesz basis but no exponential orthonormal basis. It is the first of such kind of examples.
An Extension of a Theorem of Ash on Generalized Differentiability

Let A = { b0, b1, . , bk+`; a0, a1, . , ak+` } be a system of 2(k+`+1) real numbers such that bi 6= bj for i 6= j, satisfying ∑k+` i=0 aib p i = 0 for p = 0, 1, . , k − 1 and ∑k+` i=0 aib k i = L 6= 0. It is proved that if f is measurable, and if ∑k+` i=0 aif(x + bih) = O(|h| ) as h → 0, where λ > k − 1, at each point x on a measurable set E then the Peano derivative f([λ]) exists finitely a.e. on E. This will extend a result of Ash [1]. It is further proved that if p is a positive integer ≤ k − 1 and if the upper and lower approximate Peano derivatives of f of order p are finite on a set E then f(p) exists a.e. on E.
The Inherent Geometry of the Nuclear Hamiltonian

The symmetries inherent to the nuclear version of the Schr\"odinger wave-equation are identical to the symmetries of a face-centered cubic lattice, as already noted by Wigner in 1937 in the initial development of the independent-particle model (IPM) of nuclear structure. The significance of the identity is that it implies a high-density version of the IPM that has the gross properties of a liquid-drop, rather than a diffuse, chaotic gas of nucleons. As a consequence, all of the predictive strengths of the liquid-drop model (binding energies, radii, nuclear densities, vibrational states, etc.) and the "independent-particle" predictions of the IPM (nuclear spins, parities, magnetic moments, etc.) are retained in the lattice.
Improving Neural Topic Models by Contrastive Learning with BERT

We present a general plug-and-play contrastive 001 learning framework that improves existing 002 neural topic models (NTMs) by incorporating 003 the knowledge distilled from pre-trained lan-004 guage models. Recent NTMs have been ap-005 plied to many applications and shown promis-006 ing improvement on text analysis. How-007 ever, they mainly focus on word-occurrences 008 and are often optimized by maximizing the 009 likelihood-based objective, which could lead 010 to suboptimal topic coherence and document 011 representation. To overcome the above bottle-012 neck, we introduce an additional contrastive 013 loss that pushes the topical representation of 014 a document learned by an NTM close to the 015 semantic representation of the document ob-016 tained from pre-trained language models. In 017 this way, the prior knowledge of the pre-018 trained language models can enrich the contex-019 tual information of the target corpus for NTMs. 020 Comprehensive experiments show that the pro-021 posed framework achieve the state-of-the-art 022 performance. Importantly, our framework is 023 general approach to improve most of the exist-024 ing NTMs. 025
Bifurcation of Macroeconometric Models and Robustness of Dynamical Inferences

In systems theory, it is well known that the parameter spaces of dynamical systems are stratified into bifurcation regions, with each supporting a different dynamical solution regime. Some can be stable, with different characteristics, such as monotonic stability, periodic damped stability, or multiperiodic damped stability, and some can be unstable, with different characteristics, such as periodic, multiperiodic, or chaotic unstable dynamics. But in general the existence of bifurcation boundaries is normal and should be expected from most dynamical systems, whether linear or nonlinear. Bifurcation boundaries in parameter space are not evidence of model defect. While existence of such bifurcation boundaries is well known in economic theory, econometricians using macroeconometric models rarely take bifurcation into consideration, when producing policy simulations from macroeconometrics models. Such models are routinely simulated only at the point estimates of the models' parameters.
MILLIMETER MULTIPLICITY IN DR21(OH): OUTFLOWS, MOLECULAR CORES, AND ENVELOPES

We present sensitive high angular resolution (∼1″) millimeter continuum and line observations from the massive star-forming region DR21(OH) located in the Cygnus X molecular cloud. Within the well-known dusty MM1–2 molecular cores, we report the detection of a new cluster of about 10 compact continuum millimeter sources with masses between 5 and 24 M☉, and sizes of a few thousands of astronomical units. These objects are likely to be large dusty envelopes surrounding massive protostars, some of them most probably driving several of the outflows that emanate from this region. Additionally, we report the detection of strong millimeter emission of formaldehyde (H2CO) and methanol (CH3OH) near 218 GHz as well as compact emission from the typical outflow tracers carbon monoxide and silicon monoxide (CO and SiO) toward this massive star-forming region. The H2CO and CH3OH emission is luminous (∼10−4L☉), well resolved, and found along the collimated methanol maser outflow first identified at centimeter wavelengths and in the sources SMA6 and SMA7. Our observations suggest that this maser outflow might be energized by a millimeter source called SMA4 located in the MM2 dusty core. The CO and SiO emission traces some other collimated outflows that emanate from MM1–2 cores, and are not related with the low-velocity maser outflow.
Fault Diagnosis Scheme for Open-Circuit Fault in N+2 Converter of Six-Phase SRM Using Midpoint Current Spectrum Analysis

In this paper, a six-phase $\text{N}+2$ power converter for switched reluctance motor is studied. An open-circuit fault diagnosis and faulty devices location scheme based on midpoint current spectrum analysis is proposed. In order to realize fault diagnosis, five fault cases are distinguished, including single-phase fault, multiphase fault and midpoint switch fault. Taking the phase current frequency as the fundamental frequency, the DC component, the fundamental frequency component, and the second harmonic component have different change rules in the five fault cases. The third harmonic component is used as the denominator, three spectrum coefficient could be obtained and be used as the fault characteristic. Through this scheme, using a single current sensor to detect the midpoint current can ensure open-circuit faults accurately. After the fault case is confirmed, the amplitude of the harmonic component is used to define a fault location threshold, and the threshold is numerically compared with the midpoint current to realize the faulty bridge arm location. Finally, the complete process of fault diagnosis and location is described, then the effectiveness of the proposed diagnosis method is validated by the simulation and experiment.
Comparison of intracranial pressure changes in out-of-hospital cardiac arrest patients with and without malignant blood-brain barrier disruption

Objective In the present study, intracranial pressure (ICP) changes were investigated in out-ofhospital cardiac arrest (OHCA) patients with and without malignant blood-brain barrier (BBB) disruption who underwent target temperature management. Methods This prospective, single-center, observational study was conducted from June 2019 to December 2021. ICP and albumin quotient values were measured on days 1, 2, 3, and 4 of hospitalization. Malignant BBB disruption was defined as the sum of scores for the degree of BBB disruption ≥9 on days 1 to 4. Results ICP in OHCA patients without malignant BBB disruption on days 1, 2, 3, and 4 of hospitalization was 9.58±0.53, 12.32±0.65, 14.39±0.76, and 13.88±0.87 mmHg, respectively, and in OHCA patients with malignant BBB disruption 13.65±0.74, 15.72±0.67, 16.10±0.92, and 15.22±0.87 mmHg, respectively (P<0.001, P<0.001, P=0.150, and P=0.280, respectively). The P-values of changes in ICP between days 1 and 2, days 2 and 3, and days 3 and 4 of hospitalization in OHCA patients without malignant BBB disruption were P<0.001, P=0.001, and P=0.540, respectively, and in OHCA patients with malignant BBB disruption were P=0.002, P=0.550, and P=0.100, respectively. Conclusion Among OHCA patients treated with target temperature management, ICP was higher on days 1 and 2 of hospitalization and an increase in ICP occurred earlier with malignant BBB disruption than without malignant BBB disruption.