Miracle-dz/UniFAR-FTUs huggingface dataset:
MAGNETIC FIELDS IN EARLY PROTOSTELLAR DISK FORMATION

We consider formation of accretion disks from a realistically turbulent molecular gas using 3D MHD simulations. In particular, we analyze the effect of the fast turbulent reconnection described by the Lazarian & Vishniac model for the removal of magnetic flux from a disk. With our numerical simulations we demonstrate how the fast reconnection enables protostellar disk formation resolving the so-called “magnetic braking catastrophe. ” In particular, we provide a detailed study of the dynamics of a 0.5 M⊙ protostar and the formation of its disk for up to several thousands years. We measure the evolution of the mass, angular momentum, magnetic field, and turbulence around the star. We consider effects of two processes that strongly affect the magnetic transfer of angular momentum, both of which are based on turbulent reconnection: the first, “reconnection diffusion,” removes the magnetic flux from the disk; the other involves the change of the magnetic field's topology, but does not change the absolute value of the magnetic flux through the disk. We demonstrate that for the first mechanism, turbulence causes a magnetic flux transport outward from the inner disk to the ambient medium, thus decreasing the coupling of the disk to the ambient material. A similar effect is achieved through the change of the magnetic field's topology from a split monopole configuration to a dipole configuration. We explore how both mechanisms prevent the catastrophic loss of disk angular momentum and compare both above turbulent reconnection mechanisms with alternative mechanisms from the literature.
Evaluating vacant middle seats and masks as Coronavirus exposure reduction strategies in aircraft cabins using particle tracer experiments and computational fluid dynamics simulations

Aircraft cabins have high‐performance ventilation systems, yet typically hold many persons in close proximity for long durations. The current study estimated airborne virus exposure and infection reductions when middle seats are vacant compared to full occupancy and when passengers wear surgical masks in aircraft. Tracer particle data reported by U.S. Transportation Command (TRANSCOM) and CFD simulations reported by Boeing were used along with NIOSH data, to build nonlinear regression models with particle exposure and distance from particle source as variables. These models that estimate exposure at given distances from the viral source were applied to evaluate exposure reductions from vacant middle seats. Reductions averaged 54% for the seat row where an infectious passenger is located and 36% for a 24‐row cabin containing one infectious passenger, with middle seats vacant. Analysis of the TRANSCOM data showed that universal masking (surgical masks) reduced exposures by 62% and showed masking and physical distancing provide further reductions when practiced together. For a notional scenario involving 10 infectious passengers, compared with no intervention, masking, distancing, and both would prevent 6.2, 3.8, and 7.6 secondary infections, respectively, using the Wells–Riley equation. These results suggest distancing alone, masking alone, and these practiced together reduce SARS CoV‐2 exposure risk in increasing order of effectiveness, when an infectious passenger is present.
Asymmetric Dark Matter from a GeV Hidden Sector

Asymmetric Dark Matter (ADM) models relate the dark matter density to the baryon asymmetry, so that a natural mass scale for ADM is around a few GeV. In existing models of ADM, this mass scale is unexplained; here we generate this GeV scale for dark matter (DM) from the weak scale via gauge kinetic mixing with a new Abelian dark force. In addition, this dark sector provides an efficient mechanism for suppressing the symmetric abundance of DM through annihilations to the dark photon. We augment this sector with a higher dimensional operator responsible for communicating the baryon asymmetry to the dark sector. Our framework also provides DM candidate for gauge mediation models. It results in a direct detection cross section of interest for current experiments: sigma less than or similar to 10^{-42} cm^2 for DM masses in the range 1 - 15 GeV.
Nonorientable Lagrangian surfaces in rational
4–manifolds

We show that for any nonzero class $A$ in $H_2(X; \mathbb{Z}_2)$ in a rational 4-manifold $X$, $A$ is represented by a nonorientable embedded Lagrangian surface L (for some symplectic structure) if and only if $P(A)\equiv (L) (mod\ 4)$; where $P(A)$ denotes the mod 4 valued Pontrjagin square of $A$.
Constrained Dirac gluino mediation

We perform a comparison study of the Constrained Minimal Supersymmetric Standard Model and Constrained General Gauge Mediation with and without a heavy Dirac gluino. These extremely simple models have very few free parameters and exhibit the characteristic features of supersoftness and supersafeness. We determine the characteristic low energy spectra, the production cross sections of key processes at the Large Hadron Collider and the degree of fine tuning for a representative range of parameters for each model.
Simple signature-based Groebner basis algorithm

This paper presents an algorithm for computing Groebner bases based upon labeled polynomials and ideas from the algorithm F5. The main highlights of this algorithm compared with analogues are simplicity both of the algorithm and of the its correctness proof achieved without loss of the efficiency. This leads to simple implementation which performance is in par with more complex analogues
Exact two-time correlation and response functions in the one-dimensional coagulation–diffusion process by the empty-interval method

The one-dimensional coagulation–diffusion process describes the strongly fluctuating dynamics of particles, freely hopping between the nearest-neighbour sites of a chain, such that one of them disappears with probability one if two particles meet. The exact two-time correlation and response functions in the one-dimensional coagulation–diffusion process are derived from a generalization of the empty-interval method. The main quantity is the conditional probability of finding an empty interval of n consecutive sites, if at distance d a site is occupied by a particle. Closed equations of motion are derived such that the probabilities needed for the calculation of correlators and responses, respectively, are distinguished by different initial and boundary conditions. In this way, the dynamical scaling of these two-time observables is analysed in the long-time ageing regime. A new generalized fluctuation-dissipation ratio with a universal and finite limit is proposed.
An Extended Variational Principle for the SK Spin-Glass Model

The recent proof by F. Guerra that the Parisi ansatz provides a lower bound on the free energy of the SK spin-glass model could have been taken as oﬀering some support to the validity of the purported solution. In this work we present a broader variational principle, in which the lower bound, as well as the actual value, are expressed through an optimization procedure for which ultrametic/hierarchal structures form only a subset of the variational class. The validity of Parisi’s ansatz for the SK model is still in question. The new variational principle may be of help in critical review of the issue.
THE WISE DETECTION OF AN INFRARED ECHO IN TIDAL DISRUPTION EVENT ASASSN-14li

We report the detection of a significant infrared variability of the nearest tidal disruption event (TDE) ASASSN-14li using Wide-field Infrared Survey Explorer and newly released Near-Earth Object WISE Reactivation data. In comparison with the quiescent state, the infrared flux is brightened by 0.12 and 0.16 mag in the W1 (3.4 μm) and W2 (4.6 μm) bands at 36 days after the optical discovery (or ∼110 days after the peak disruption date). The flux excess is still detectable ∼170 days later. Assuming that the flare-like infrared emission is from the dust around the black hole, its blackbody temperature is estimated to be ∼2.1 × 103 K, slightly higher than the dust sublimation temperature, indicating that the dust is likely located close to the dust sublimation radius. The equilibrium between the heating and radiation of the dust claims a bolometric luminosity of ∼1043–1045 erg s−1, comparable with the observed peak luminosity. This result has for the first time confirmed the detection of infrared emission from the dust echoes of TDEs.
Optimal Control for Multiscale Elliptic Equations with Rough Coefficients

This paper concerns the convex optimal control problem governed by multiscale elliptic equations with arbitrarily rough $L^\infty$ coefficients, which has important applications in composite materials and geophysics. We use one of the recently developed numerical homogenization techniques, the so-called Rough Polyharmonic Splines (RPS) and its generalization (GRPS) for the efficient resolution of the elliptic operator on the coarse scale. Those methods have optimal convergence rate which do not rely on the regularity of the coefficients nor the concepts of scale-separation or ergodicity. As the iterative solution of the OCP-OPT formulation of the optimal control problem requires solving the corresponding (state and co-state) multiscale elliptic equations many times with different right hand sides, numerical homgogenization approach only requires one-time pre-computation on the fine scale and the following iterations can be done with computational cost proportional to coarse degrees of freedom. Numerical experiments are presented to validate the theoretical analysis.
Phase diagrams of voltage-gated oxide interfaces with strong Rashba coupling

We propose a model for the two-dimensional electron gas formed at the interface of oxide heterostructures that includes a Rashba spin-orbit coupling proportional to an electric field oriented perpendicularly to the interface. Taking into account the electron density dependence of this electric field confining the electron gas at the interface, we report the occurrence of a phase separation instability (signaled by a negative compressibility) for realistic values of the spin-orbit coupling and of the electronic band-structure parameters at zero temperature. We extend the analysis to finite temperatures and in the presence of an in-plane magnetic field, thereby obtaining two phase diagrams that exhibit a phase separation dome. By varying the gating potential, the phase separation dome may shrink and vanish at zero temperature into a quantum critical point where the charge fluctuates dynamically. Similarly, the phase separation may be spoiled by a planar magnetic field even at zero temperature leading to a line of quantum critical points.
Reconstructing directed graphs from generalized gauge actions on their Toeplitz algebras

Abstract We show how to reconstruct a finite directed graph E from its Toeplitz algebra, its gauge action, and the canonical finite-dimensional abelian subalgebra generated by the vertex projections. We also show that if E has no sinks, then we can recover E from its Toeplitz algebra and the generalized gauge action that has, for each vertex, an independent copy of the circle acting on the generators corresponding to edges emanating from that vertex. We show by example that it is not possible to recover E from its Toeplitz algebra and gauge action alone.
Virtual push-forwards

Let $p:F\to G$ be a morphism of stacks of positive \emph{virtual} relative dimension $k$ and let $\gamma\in H^k(F)$. We give sufficient conditions for $p_*\gamma\cdot[F]^{virt}$ to be a multiple of $[G]^{virt}$. We apply this result to show an analogue of the conservation of number for virtually smooth families. We show implications to Gromov-Witten invariants and give a new proof of a theorem of Marian, Oprea and Pandharipande which compares the virtual classes of moduli spaces of stable maps and moduli spaces of stable quotients.
Disk, merger, or outflow ? Molecular gas kinematics in two powerful obscured QSOs at z>3.4

We report on the detection of bright CO(4-3) line emission in two powerful, obscured quasars discovered in the SWIRE survey, SW022513 and SW022550 at z≥3.4. We analyze the line strength and profile to determine the gas mass, dynamical mass and the gas dynamics for both galaxies. In SW022513 we may have found the first evidence for a molecular, AGN-driven wind in the ear ly Universe. The line profile in SW022513 is broad (FWHM = 1000 km s −1 ) and blueshifted by−200 km s −1 relative to systemic (where the systemic velocity is estimated from the narrow components of ionized gas lines, as is commonly done for AGN at low and high redshifts). SW022550 has a more regular, double-peaked profile, which is marginally spatially resolved in our data, con sistent with either a merger or an extended disk. The molecular gas masses, 4×10 10 M⊙, are large and account for<30% of the stellar mass, making these obscured QSOs as gas rich as other powerful CO emitting galaxies at high redshift, i.e., submillimeter galaxies. Our sources exhibit relatively lo wer star-formation effi ciencies compared to other dusty, powerful starburst galax ies at high redshift. We speculate that this could be a consequence of the AGN perturbing the molecular gas.
PULSARS: GIGANTIC NUCLEI

What is the real nature of pulsars? This is essentially a question of the fundamental strong interaction between quarks at low-energy scale and hence of the non-perturbative quantum chromo-dynamics, the solution of which would certainly be meaningful for us to understand one of the seven millennium prize problems (i.e., "Yang-Mills Theory") named by the Clay Mathematical Institute. After a historical note, it is argued here that a pulsar is very similar to an extremely big nucleus, but is a little bit different from the gigantic nucleus speculated 80 years ago by L. Landau. The paper demonstrates the similarity between pulsars and gigantic nuclei from both points of view: the different manifestations of compact stars and the general behavior of the strong interaction.
Characterisation of sets of limit measures after iteration of a cellular automaton on an initial measure

The asymptotic behavior of a cellular automaton iterated on a random configuration is well described by its limit probability measure(s). In this paper, we characterize measures and sets of measures that can be reached as limit points after iterating a cellular automaton on a simple initial measure, in the same spirit as SRB measures. In addition to classical topological constraints, we exhibit necessary computational obstructions. With an additional hypothesis of connectivity, we show these computability conditions are sufficient by constructing a cellular automaton realising these sets, using auxiliary states in order to perform computations. Adapting this construction, we obtain a similar characterization for the Ces\`aro mean convergence, a Rice theorem on the sets of limit points, and we are able to perform computation on the set of measures, i.e. the cellular automaton converges towards a set of limit points that depends on the initial measure. Last, under non-surjective hypotheses, it is possible to remove auxiliary states from the construction.
Rural teacher attitudes and engagement with computing and technology

The purpose of this sequential Case Study-Mixed Methods research is to explore rural teacher attitudes toward, approaches to, and engagement with making and computational thinking during STEM professional development and co-teaching learning experiences. Specifically, we examine the professional learning needs of two rural, middle school teachers as they engage technology. Using the lens of cultural historical activity theory, this paper examines the ways in which teacher attitude about computing shifted throughout professional learning and instructional practice. Findings show three broad themes that emerge surrounding teacher attitudes, approaches, and engagement with technology: Anxiety, Independent Learner, and Integration. Additionally, findings suggest that teacher attitude toward technology can be moderated through the means of a more knowledgeable other who scaffolds teacher learning and integration of technology.
Zeno-line, Binodal, T-{\rho} Diagram and Clusters as a new Bose-Condensate Bases on New Global Distributions in Number Theory

We present the correspondence principle between the T-{\rho} diagram, the Zeno line and the binodal for a given interaction potential of Lennard-Jones type. We use this correspondence further to construct a distribution of the Bose-Einstein type for a classical gas with the help of the new notion of Bose condensate, making it possible to decrease fractal dimension while simultaneously preserving the number of particles. In so doing, we use new global distributions in number theory.
Researching vulnerable participants: The role of critical reflexivity in overcoming methodological challenges

In this paper, we critically reflect on the methodological challenges encountered during a qualitative research project that examined the effectiveness of the Australian National Disability Insurance Scheme (NDIS). We draw on Lewis and Mehmet’s (2021) approach that combines aspects of autoethnography and reflexivity to focus on three key areas, inclusive research, informed consent, and recruitment, which we have considered in terms of mistrust and the roles of the gatekeeper. This paper contributes to our understanding of researching vulnerable and marginalised populations and highlights learnings for marketers as they seek to identify how to adequately capture the voices of the often voiceless. Key implications include acknowledging vulnerability as a multi-dimensional concept, adopting a continual reflective approach, selecting appropriate channels of communication, and considering team dynamics before and during research implementation. By showcasing our learning experiences, we guide other market researchers who are interested in exploring similarly marginalised or vulnerable groups.
Impact of Green Servant Leadership on Organizational Sustainability: The Mediating Role of Green Human Resource Management Practices

Green human resource management practices in the presence of green servant leadership have become a prime business concern for sustainable growth. This study examines the mediating role of green HRM practices between green Servant leadership and sustainable firm performance, particularly in the manufacturing sector. Cross-sectional data were collected from 480 owners/human resource managers working in the manufacturing industry in Pakistan using a convenient sampling technique. A partial least squares approach was applied to test the hypothesized relationships. The research findings suggest that Green Servant leadership and Sustainable Firm Performance are mediated by Green Human Resource Management Practices (GHRM). This empirical study contributes to the literature by considering GHRM as a mediator using the theoretical lens of stakeholder theory and resource-based view.
Minimal decaying Dark Matter and the LHC

We consider a minimal Dark Matter model with just two additional states, a Dark Matter Majorana fermion and a colored or electroweakly charged scalar, without introducing any symmetry to stabilize the DM state. We identify the parameter region where an indirect DM signal would be within the reach of future observations and the DM relic density generated fits the observations. We find in this way two possible regions in the parameter space, corresponding to a FIMP/SuperWIMP or a WIMP DM. We point out the different collider signals of this scenario and how it will be possible to measure the different couplings in case of a combined detection.
Influence Mechanism of Rubber Thermal Oxygen Aging on Dynamic Stiffness and Loss Factor of Rubber Isolation Pad

The influence mechanism of thermal oxygen aging on the dynamic characteristic of the rubber isolation pad (RIP) is usually ignored in studies. However, the ambient temperature of the RIP could reach up to 70°C in general, and even 108°C under some extreme conditions, which will lead to accelerated thermal oxygen aging and a decline in the mechanical performance for the RIP. In the meantime, the thermal oxygen aging will result in excessive vibration and even a damaged external air conditioner. Therefore, the research on the influence mechanism of rubber thermal oxygen aging on the dynamic performances of the RIP is crucial to the mechanical characteristic matching of the RIP. Considering the effect of the thermal oxygen aging on the dynamic characteristic, a novel model of thermal oxygen aging-dynamic characteristic of the RIP is established by adopting the Peck model, the hyperelastic model, the fractional derivative model, and the smooth Coulomb friction model (SCFM) in this paper. A test rig of the static and dynamic characteristics of the RIP is built, and an identification method of model parameters is developed based on the MTS831 elastomer test system as well which of the thermal oxygen aging-dynamic characteristic model is verified by the experimental data. The result is shown that the maximum growth rate of the static stiffness and the dynamic stiffness is 20.7% and 4.5%, respectively, and the maximum decrease rate of the loss factor is 10.6% as the thermal oxygen aging hardness of the RIP increases by 5HA. The amplitude-dependent, frequency-dependent, and thermal oxygen aging-dependent performances of the RIP are effectively characterized by the thermal oxygen aging-dynamic characteristic model. Moreover, a theoretical foundation is provided for the evolution law of the dynamic characteristic of the RIP after the service with the thermal oxygen aging condition in this research.
A more general framework for coGalois theory

The paper is an extended version of a talk given at the International Conference: Experimental and Theoretical Methods in Algebra, Geometry and Topology, which took place June 21--24, 2013 in Eforie Nord (Romania). Its purpose is to present a more general framework for a fairly new theory in Field Theory, called coGalois Theory, which is somewhat dual to the very classical Galois Theory and is more general than the Kummer Theory. The main object of investigation in this more general framework is the coGalois connexion naturally associated to any triple $\,(\Gamma, \frak{G}, \eta)\,$, where $\,\Gamma\,$ is a profinite group, $\,\frak{G}\,$ is a profinite operator $\,\Gamma$-group, and $\,\eta: \Gamma \longrightarrow \frak{G}\,$ is a continuous $\,1$-cocycle with the property that the profinite group $\,\frak{G}\,$ is topologically generated by the image $\,\eta(\Gamma)$.
Elliptic law for real random matrices

In this paper we consider ensemble of random matrices $\X_n$ with independent identically distributed vectors $(X_{ij}, X_{ji})_{i \neq j}$ of entries. Under assumption of finite fourth moment of matrix entries it is proved that empirical spectral distribution of eigenvalues converges in probability to a uniform distribution on the ellipse. The axis of the ellipse are determined by correlation between $X_{12}$ and $X_{21}$. This result is called Elliptic Law. Limit distribution doesn't depend on distribution of matrix elements and the result in this sence is universal.