Miracle-dz/UniFAR-FTUs huggingface dataset:
Photon production and elliptic flow from a momentum-anisotropic quark-gluon plasma

The emission of real photons from a momentum-anisotropic quark-gluon plasma (QGP) is affected by both the collective flow of the radiating medium and the modification of local rest frame emission rate due to the anisotropic momentum distribution of partonic degrees of freedom. In this paper, we first calculate the photon production rate from an ellipsoidally momentum-anisotropic QGP including hard contributions from Compton scattering and quark pair annihilation and soft contribution calculated using the hard thermal loop (HTL) approximation. We introduce a parametrization of the nonequilibrium rate in order to facilitate its further application in yield and flow calculations. We convolve the anisotropic photon rate with the space-time evolution of QGP provided by 3+1d anisotropic hydrodynamics (aHydro) to obtain the yield and the elliptic flow coefficient $v_2$ of photons from QGP generated at Pb-Pb collisions at LHC at 2.76 TeV and Au-Au collisions at RHIC at 200 GeV. We investigate the effects of various parameters on the results. In particular we analyze the sensitivity of results to initial momentum anisotropy.
ERASER: A Benchmark to Evaluate Rationalized NLP Models

State-of-the-art models in NLP are now predominantly based on deep neural networks that are opaque in terms of how they come to make predictions. This limitation has increased interest in designing more interpretable deep models for NLP that reveal the ‘reasoning’ behind model outputs. But work in this direction has been conducted on different datasets and tasks with correspondingly unique aims and metrics; this makes it difficult to track progress. We propose the Evaluating Rationales And Simple English Reasoning (ERASER a benchmark to advance research on interpretable models in NLP. This benchmark comprises multiple datasets and tasks for which human annotations of “rationales” (supporting evidence) have been collected. We propose several metrics that aim to capture how well the rationales provided by models align with human rationales, and also how faithful these rationales are (i.e., the degree to which provided rationales influenced the corresponding predictions). Our hope is that releasing this benchmark facilitates progress on designing more interpretable NLP systems. The benchmark, code, and documentation are available at https://www.eraserbenchmark. com/
An Energy Bound in the Affine Group

We prove a nontrivial energy bound for a finite set of affine transformations over a general field and discuss a number of implications. These include new bounds on growth in the affine group, a quantitative version of a theorem by Elekes about rich lines in grids. We also give a positive answer to a question of Yufei Zhao that for a plane point set $P$ for which no line contains a positive proportion of points from $P$, there may be at most one line, meeting the set of lines defined by $P$ in at most a constant multiple of $|P|$ points.
Efficacy of Aggression Replacement Training among Children from North-West Russia

The aim of the study was to assess whether the Aggr ession Replacement Training (ART) programme is effective in increasing social skills and decreasing problem behaviour. The sample consisted of 232 children (mean age 10.9 yrs , SD = 2.32), their parents and teachers. The study had a quasi-experimental design with intervention and control groups. Children were recruited from six schools an d four social institutions from four regions in North-West Russia from 2010 to 2013. Social skills and externalizing behaviour were assessed with the Social Skills Rating Scale and analyzed by repeated measures ANOVA (GLM). In a pre and post-test assessment, the 30-hour ART programme was associated with a significant increas e in social skills when assessed by children’s self-reports. The most reliable effects of the intervention were demonstrated in the two age groups of 6-9 and 10-14 years old. When both pre and post-test were assessed by parents and teachers, children from bot h the intervention and control groups demonstrated more social skills and less problem be haviour. Overall results point to a significant improvement of social skills among chil dren from the intervention groups, but an improvement in social skills and reduction o f problem behaviour have also been indicated among children from the control group. Fi ndings are discussed in view to possible diffusion of treatment from children parti cipating in an intervention to children from control groups.
Geometry and flexibility of optimal catalysts in a minimal elastic network model

We have a general knowledge of the principles by which catalysts accelerate the rate of chemical reactions but no precise understanding of the geometrical and physical constraints to which their design is subject. To analyze these constraints, we introduce a minimal model of catalysis based on elastic networks where the implications of the geometry and flexibility of a catalyst can be studied systematically. The model demonstrates the relevance and limitations of the principle of transition-state stabilization: optimal catalysts are found to have a geometry complementary to the transition state but a degree of flexibility that non-trivially depends on the parameters of the reaction as well as on external parameters such as the concentrations of reactants and products. The results illustrate how simple physical models can provide valuable insights on the design of catalysts.
Pliability and Approximating Max-CSPs

We identify a sufficient condition, treewidth-pliability, that gives a polynomial-time algorithm for an arbitrarily good approximation of the optimal value in a large class of Max-2-CSPs parameterised by the class of allowed constraint graphs (with arbitrary constraints on an unbounded alphabet). Our result applies more generally to the maximum homomorphism problem between two rational-valued structures. The condition unifies the two main approaches for designing a polynomial-time approximation scheme. One is Baker’s layering technique, which applies to sparse graphs such as planar or excluded-minor graphs. The other is based on Szemerédi’s regularity lemma and applies to dense graphs. We extend the applicability of both techniques to new classes of Max-CSPs. However, we prove that the condition cannot be used to find solutions (as opposed to approximating the optimal value) in general. Treewidth-pliability turns out to be a robust notion that can be defined in several equivalent ways, including characterisations via size, treedepth, or the Hadwiger number. We show connections to the notions of fractional-treewidth-fragility from structural graph theory, hyperfiniteness from the area of property testing, and regularity partitions from the theory of dense graph limits. These may be of independent interest. In particular, we show that a monotone class of graphs is hyperfinite if and only if it is fractionally-treewidth-fragile and has bounded degree.
Dynamics of curved travelling fronts for the discrete Allen-Cahn equation on a two-dimensional lattice

In this paper we consider the discrete Allen-Cahn equation posed on a two-dimensional rectangular lattice. We analyze the large-time behaviour of solutions that start as bounded perturbations to the well-known planar front solution that travels in the horizontal direction. In particular, we construct an asymptotic phase function $\gamma_j(t)$ and show that for each vertical coordinate $j$ the corresponding horizontal slice of the solution converges to the planar front shifted by $\gamma_j(t)$. We exploit the comparison principle to show that the evolution of these phase variables can be approximated by an appropriate discretization of the mean curvature flow with a direction-dependent drift term. This generalizes the results obtained in [Matano & Nara, 2011] for the spatially continuous setting. Finally, we prove that the horizontal planar wave is nonlinearly stable with respect to perturbations that are asymptotically periodic in the vertical direction.
Title: Contributions of Ammonia-Oxidizing Bacteria and Archaea to Nitrification in Forest Soils.

approved: _____________________________________________________________________ David D. Myrold Prior to 2005, ammonia oxidation, the first step of nitrification, was thought mediated mainly by ammonia-oxidizing bacteria (AOB). However, the discovery of Thaumarchaeota carrying the genes coding for the ammonia monooxygenase (AMO) enzyme led to the discovery that ammonia-oxidizing archaea (AOA) also contribute to nitrification. Despite the uptick in studies on nitrification following the recognition of AOA, the relative importance and the contribution of AOA and AOB in different ecosystems, and the factors controlling their abundance and activity, have not been well understood. Because nitrogen (N) cycling is mediated by microbes and controls the net primary productivity in forests, and nitrification is the rate controlling step in N cycling, it is important to have a better understanding of nitrification in forest ecosystem, especially the abundance and contribution of AOA and AOB in forest soils. The objective of this study was to determine nitrification activity and nitrifier abundance in forest soils. I wanted to know: (i) if the inclusion of red alder influences the distribution, total nitrification activity, and relative contribution of AOA and AOB to nitrification; (ii) if pH and substrate concentration influence the distribution and activity of ammonia oxidizers, and if so, (iii) what is the relationship between these two factors and nitrification. The study selected soils from stands of red alder (Alnus rubra Bong.) and Douglas-fir (Pseudotsuga menziesii Mirb. Franco) at three sites in Oregon (Cascade Head, the H.J. Andrews, and McDonald Forest) that had a soil pH range of 3.9 to 5.7. The abundances of AOA and AOB were investigated using quantitative PCR (qPCR) by targeting the amoA gene. Nitrification activity was evaluated by nitrification potential in a slurry assay and nitrification rate in whole soil. Activity of AOA and AOB was differentiated by using octyne, which inhibits the AMO enzyme in AOB but not AOA. Nitrification activity and octyne-resistant activity (AOA) were significantly higher at Cascade Head than at the H.J. Andrews and McDonald Forest and greater in red alder compared with Douglas-fir soils. Whole soil nitrification rate was stimulated by high NH3 concentration (10 mmol kg -1 soil) addition but not by low NH3 concentration (1 mmol kg -1 soil). At the high concentration of NH3, both AOA and AOB responded, and nitrification was highest at McDonald Forest, followed by Cascade Head and the H.J. Andrews. There was strong evidence that soil pH was an important factor controlling AOA but not AOB abundance, and the AOA to AOB ratio decreased with increasing soil pH. Collectively, the data indicated that nitrification was mainly driven by AOA in acidic forest soils (pH < 5). ©Copyright by Xinda Lu June 5, 2014 All Rights Reserved Contributions of Ammonia-Oxidizing Bacteria and Archaea to Nitrification in Forest Soils
Instabilities in modified theories of gravity

The review is devoted to consideration of possible observational consequences of modified gravity theories, suggested for explanation of the contemporary accelerated expansion of the universe. The major attention is paid to F(R)-models. It is shown that in systems with rising energy density high frequency and large amplitude oscillations of the curvature scalar, R(t), are induced. These oscillations lead to the production of elementary particles, which may be observed in the spectra of energetic cosmic rays. In the background of such oscillating solutions gravitation repulsion between finite-size objects becomes possible. Since the Lagrangian is a non-linear function of curvature, equations of motion become of higher (4th) order and exhibit very rich pattern of new physical effects. In particular, the evolution of density perturbations is strongly different from that in General Relativity, amplified due to both parametric resonance and anti-friction phenomena.
CAPABILITIES OF GOVERNMENTAL PURCHASERS IN THE USA

The main purpose of this paper is the evaluation of previous German and Spanish research conducted related to oral communication capability in a different cultural surrounding. In order to test the validity of the European findings, a new sample was drawn using membership data of the U.S. based National Institute of Governmental Purchasing. The results of this paper corroborate that oral communication capability is a construct consisting of three dimensions. The model obtained in Europe for managers from private sector purchasers is also applicable in the U.S. for public purchasers. Furthermore, European results proposed four distinct types of communicators, while in the U.S. two additional groups of purchasers were found. Nevertheless, there is limited evidence for demographic or cultural influences on the oral communication capabilities of purchasers.
Characterization of the human GYS2 gene and its product using bioinformatic tools

Aim: The GYS2 gene, which encodes for glycogen synthase 2 (liver) (GS), is an enzyme responsible for the synthesis of 1,4-linked glucose chains in glycogen. The present study aimed to investigate the homology, conserved domain, and promoter and expression profiles of the human GYS2 gene among various vertebrate species using bioinformatic tools. Materials and Methods: We analyzed the homology with NCBI blast, the conserved domain with EBI ClustalW and Mega4, the promoter with Genomatix, and the expression profiles with DigiNorthern software. Results: GS proteins and their conserved domains (Glycogen-syn) were more conserved in all the organisms investigated. There was 1 fully conserved domain (Glycogen-syn) and several truncated sub-domains. Comparative screening of the promoters showed that GYS2 genes did not have any common conserved transcription factor binding sites. Conclusions: This study shows that the GS molecules in various species, except Ornithorhynchus anatinus and Danio rerio, were well conserved throughout evolution.
The star formation timescale of elliptical galaxies

The alpha element to iron peak element ratio, for example [Mg/Fe], is a commonly applied indicator of the galaxy star formation timescale (SFT) since the two groups of elements are mainly produced by different types of supernovae that explode over different timescales. However, it is insufficient to consider only [Mg/Fe] when estimating the SFT. The [Mg/Fe] yield of a stellar population depends on its metallicity. Therefore, it is possible for galaxies with different SFTs and at the same time different total metallicity to have the same [Mg/Fe]. This effect has not been properly taken into consideration in previous studies. In this study, we assume the galaxy-wide stellar initial mass function (gwIMF) to be canonical and invariant. We demonstrate that our computation code reproduces the SFT estimations of previous studies, where only the [Mg/Fe] observational constraint is applied. We then demonstrate that once both metallicity and [Mg/Fe] observations are considered, a more severe “downsizing relation” is required. This means that either low-mass ellipticals have longer SFTs (> 4 Gyr for galaxies with mass below 1010 M⊙) or massive ellipticals have shorter SFTs (≈200 Myr for galaxies more massive than 1011 M⊙) than previously thought. This modification increases the difficulty in reconciling such SFTs with other observational constraints. We show that applying different stellar yield modifications does not relieve this formation timescale problem. The quite unrealistically short SFT required by [Mg/Fe] and total metallicity would be prolonged if a variable stellar gwIMF were assumed. Since a systematically varying gwIMF has been suggested by various observations this could present a natural solution to this problem.
Service quality in Medellin hotels using perceptual maps

The online comments and assessments made by hotel customers provide relevant information to determine the various dimensions of the service received. In this context, the purpose of this work is to evaluate the quality perceived by national and international guests staying at different hotels in Medellín (Colombia). To this end, the multidimensional scaling technique of perceptual maps was used to apply to 9,153 comments made on the TripAdvisor platform to 57 hotels between 2005 and 2010. The main finding shows that the factors most valued by guests are cleanliness, quality of rest and service above the location, price and comfort of the rooms, although these factors differ according to the characteristics of the visitor and the hotel.
Acceleration of superrotation in simulated hot Jupiter atmospheres

Context. Atmospheric superrotating flows at the equator are a nearly ubiquitous result when conducting simulations of hot Jupiters. One theory explaining how this zonally-coherent flow reaches equilibrium has already been developed in the literature. This understanding, however, relies on the existence of either an initial superrotating flow or a sheared flow, coupled with a slow evolution that permits a linear steady state to be reached. Aims. A consistent physical understanding of superrotation is needed for arbitrary drag and radiative timescales, along with the relevance of taking linear steady states into account, needs to be assessed. Methods. We obtained an analytical expression for the structure, frequency, and decay rate of propagating waves in hot Jupiter atmospheres around a state at rest in the 2D shallow-water β-plane limit. We solved this expression numerically and confirmed the robustness of our results with a 3D linear wave algorithm. We then compared it with 3D simulations of hot Jupiter atmospheres and studied the nonlinear momentum fluxes. Results. We show that under strong day-night heating, the dynamics do not transit through a linear steady state when starting from an initial atmosphere in solid body rotation. We further demonstrate that nonlinear effects favor the initial spin-up of superrotation and that acceleration due to the vertical component of the eddy-momentum flux is critical to the initial development of superrotation. Conclusions. We describe the initial phases of the acceleration of superrotation, including the consideration of differing radiative and drag timescales, and we conclude that eddy-momentum-driven superrotating equatorial jets are robust, physical phenomena in simulations of hot Jupiter atmospheres.
Towards the Next Generation of Web-based Experiments : A Case Study Assessing Basic Audio Quality Following the ITU-R Recommendation BS . 1534 ( MUSHRA )

Listening tests are widely used to assess the quality of audio systems. The majority of such listening tests is conducted in controlled environments with selected participants and professional audio equipment. In the last few years, conducting listening tests over the Internet, as so called web-based experiments, has become popular. A recent study has shown that web-based experiments lead to comparable results as laboratory experiments. Until now, it was only possible to implement a limited number of listening test types as web-based experiments because web standards were missing some crucial features, e. g. sample manipulation of audio streams. With the upcoming of the Web Audio API, a much wider range of listening test types can be implemented as new audio processing features have been introduced. This paper demonstrates which new possibilities are enabled by the Web Audio API. To this end, the ITU-R Recommendation BS.1534 (MUSHRA) is taken as an example.
Feature discriminativity estimation in CNNs for transfer learning

The purpose of feature extraction on convolutional neural networks is to reuse deep representations learnt for a pre-trained model to solve a new, potentially unrelated problem. However, raw feature extraction from all layers is unfeasible given the massive size of these networks. Recently, a supervised method using complexity reduction was proposed, resulting in significant improvements in performance for transfer learning tasks. This approach first computes the discriminative power of features, and then discretises them using thresholds computed for the task. In this paper, we analyse the behaviour of these thresholds, with the purpose of finding a methodology for their estimation. After a comprehensive study, we find a very strong correlation between problem size and threshold value, with coefficient of determination above 90%. These results allow us to propose a unified model for threshold estimation, with potential application to transfer learning tasks.
Long- to short-junction crossover and field-reentrant critical current in Al/Ag-nanowires/Al Josephson junctions

We have probed the superconducting proximity effect through long high-quality monocrystalline Ag nanowires, by realizing Josephson junctions of different lengths, with different superconducting materials. Thanks to the high number of junctions probed, both the contact resistance and electron diffusion constant could be determined, enabling a comparison of the measured critical current to theoretical expectation, over the entire regime from short to long diffusive junction. Although the length dependence of the critical current is as expected, the amplitude of the $R_{N}I_c$ product is smaller than predicted by theory. We also address the magnetic field dependence of the critical current. The quasi-gaussian decay of the critical current with field expected of a long narrow junction is observed for all superconducting contacts we used except for aluminum. We present the striking non-monotonous effect of field on the critical current of junctions with aluminum contacts, and analyze it in terms of improved quasiparticle thermalization by a magnetic field.
Why Deep Transformers are Difficult to Converge? From Computation Order to Lipschitz Restricted Parameter Initialization

The Transformer translation model employs residual connection and layer normalization to ease the optimization difficulties caused by its multi-layer encoder/decoder structure. While several previous works show that even with residual connection and layer normalization, deep Transformers still have difficulty in training, and particularly a Transformer model with more than 12 encoder/decoder layers fails to converge. In this paper, we first empirically demonstrate that a simple modification made in the official implementation which changes the computation order of residual connection and layer normalization can effectively ease the optimization of deep Transformers. In addition, we deeply compare the subtle difference in computation order, and propose a parameter initialization method which simply puts Lipschitz restriction on the initialization of Transformers but can effectively ensure their convergence. We empirically show that with proper parameter initialization, deep Transformers with the original computation order can converge, which is quite in contrast to all previous works, and obtain significant improvements with up to 24 layers. Our proposed approach additionally enables to benefit from deep decoders compared to previous works which focus on deep encoders.
Macro F1 and Macro F1

The 'macro F1' metric is frequently used to evaluate binary, multi-class and multi-label classification problems. Yet, we find that there exist two different formulas to calculate this quantity. In this note, we show that only under rare circumstances, the two computations can be considered equivalent. More specifically, one formula well 'rewards' classifiers which produce a skewed error type distribution. In fact, the difference in outcome of the two computations can be as high as 0.5. Finally, we show that the two computations may not only diverge in their scalar result but also lead to different classifier rankings.