nils-herrmann/clean_scirepeval huggingface dataset:
PROBING THE PULSAR ORIGIN OF THE ANOMALOUS POSITRON FRACTION WITH AMS-02 AND ATMOSPHERIC CHERENKOV TELESCOPES

Recent observations by PAMELA, Fermi-LAT, and AMS-02 have conclusively indicated a rise in the cosmic-ray positron fraction above 10 GeV, a feature which is impossible to mimic under the paradigm of secondary positron production with self-consistent Galactic cosmic-ray propagation models. A leading explanation for the positron fraction rise is an additional source of electron–positron pairs, for example one or more mature, energetic, and relatively nearby pulsars. We point out that any one of two well-known nearby pulsars, Geminga and Monogem, can satisfactorily provide enough positrons to reproduce AMS-02 observations. A smoking-gun signature of this scenario is an anisotropy in the arrival direction of the cosmic-ray electrons and positrons, which may be detectable by existing, or future, telescopes. The predicted anisotropy level is, at present, consistent with limits from Fermi-LAT and AMS-02. We argue that the large collecting area of atmospheric Cherenkov telescopes (ACTs) makes them optimal tools for detecting such an anisotropy. Specifically, we show that much of the proton and γ-ray background which affects measurements of the cosmic-ray electron–positron spectrum with ACTs may be controlled in the search for anisotropies. We conclude that observations using archival ACT data could already constrain or substantiate the pulsar origin of the positron anomaly, while upcoming instruments (such as the Cherenkov Telescope Array) will provide strong constraints on the source of the rising positron fraction.
Asymptotically inspired moment-closure approximation for adaptive networks.

Adaptive social networks, in which nodes and network structure coevolve, are often described using a mean-field system of equations for the density of node and link types. These equations constitute an open system due to dependence on higher-order topological structures. We propose a new approach to moment closure based on the analytical description of the system in an asymptotic regime. We apply the proposed approach to two examples of adaptive networks: recruitment to a cause model and adaptive epidemic model. We show a good agreement between the improved mean-field prediction and simulations of the full network system.
Model-based Bayesian reinforcement learning for dialogue management

Reinforcement learning methods are increasingly used to optimise dialogue policies from experience. Most current techniques are model-free: they directly estimate the utility of various actions, without explicit model of the interaction dynamics. In this paper, we investigate an alternative strategy grounded in model-based Bayesian reinforcement learning. Bayesian inference is used to maintain a posterior distribution over the model parameters, reflecting the model uncertainty. This parameter distribution is gradually refined as more data is collected and simultaneously used to plan the agent’s actions. Within this learning framework, we carried out experiments with two alternative formalisations of the transition model, one encoded with standard multinomial distributions, and one structured with probabilistic rules. We demonstrate the potential of our approach with empirical results on a user simulator constructed from Wizard-of-Oz data in a human–robot interaction scenario. The results illustrate in particular the benefits of capturing prior domain knowledge with high-level rules.
Fuzzy Aggregates in Fuzzy Answer Set Programming

Fuzzy answer set programming is a declarative framework for representing and reasoning about knowledge in fuzzy environments. However, the unavailability of fuzzy aggregates in disjunctive fuzzy logic programs, DFLP, with fuzzy answer set semantics prohibits the natural and concise representation of many interesting problems. In this paper, we extend DFLP to allow arbitrary fuzzy aggregates. We define fuzzy answer set semantics for DFLP with arbitrary fuzzy aggregates including monotone, antimonotone, and nonmonotone fuzzy aggregates. We show that the proposed fuzzy answer set semantics subsumes both the original fuzzy answer set semantics of DFLP and the classical answer set semantics of classical disjunctive logic programs with classical aggregates, and consequently subsumes the classical answer set semantics of classical disjunctive logic programs. We show that the proposed fuzzy answer sets of DFLP with fuzzy aggregates are minimal fuzzy models and hence incomparable, which is an important property for nonmonotonic fuzzy reasoning.
Towards a workload for evolutionary analytics

Emerging data analysis involves the ingestion and exploration of new data sets, application of complex functions, and frequent query revisions based on observing prior query answers. We call this new type of analysis evolutionary analytics and identify its properties. This type of analysis is not well represented by current benchmark workloads. In this paper, we present a workload and identify several metrics to test system support for evolutionary analytics. Along with our metrics, we present methodologies for running the workload that capture this analytical scenario.
Potential networks, contagious communities, and understanding social network structure

In this paper we study how the network of agents adopting a particular technology relates to the structure of the underlying network over which the technology adoption spreads. We develop a model and show that the network of agents adopting a particular technology may have characteristics that differ significantly from the social network of agents over which the technology spreads. For example, the network induced by a cascade may have a heavy-tailed degree distribution even if the original network does not. This provides evidence that online social networks created by technology adoption over an underlying social network may look fundamentally different from social networks and indicates that using data from many online social networks may mislead us if we try to use it to directly infer the structure of social networks. Our results provide an alternate explanation for certain properties repeatedly observed in data sets, for example: heavy-tailed degree distribution, network densification, shrinking diameter, and network community profile. These properties could be caused by a sort of sampling bias rather than by attributes of the underlying social structure. By generating networks using cascades over traditional network models that do not themselves contain these properties, we can nevertheless reliably produce networks that contain all these properties. An opportunity for interesting future research is developing new methods that correctly infer underlying network structure from data about a network that is generated via a cascade spread over the underlying network.
Projective Compactifications and Einstein metrics

For complete affine manifolds we introduce a definition of compactification based on the projective differential geometry (i.e.\ geodesic path data) of the given connection. The definition of projective compactness involves a real parameter $\alpha$ called the order of projective compactness. For volume preserving connections, this order is captured by a notion of volume asymptotics that we define. These ideas apply to complete pseudo-Riemannian spaces, via the Levi-Civita connection, and thus provide a notion of compactification alternative to conformal compactification. For each order $\alpha$, we provide an asymptotic form of a metric which is sufficient for projective compactness of the given order, thus also providing many local examples. 
Distinguished classes of projectively compactified geometries of orders one and two are associated with Ricci-flat connections and non--Ricci--flat Einstein metrics, respectively. Conversely, these geometric conditions are shown to force the indicated order of projective compactness. These special compactifications are shown to correspond to normal solutions of classes of natural linear PDE (so-called first BGG equations), or equivalently holonomy reductions of projective Cartan/tractor connections. This enables the application of tools already available to reveal considerable information about the geometry of the boundary at infinity. Finally, we show that metrics admitting such special compactifications always have an asymptotic form as mentioned above.
Origins and evolutionary genomics of the novel 2013 avian-origin H7N9 influenza A virus in China: Early findings

In March and early April 2013, a new avian-origin influenza A (H7N9) virus (A-OIV) emerged in the eastern China. During the first week of April, the 18 infection cases have been confirmed and 6 people have died since March. This virus has caused global concern as a potential pandemic threat. Here we use evolutionary analysis to reconstruct the origins and early development of the A-OIV viruses. We found that A-OIV was derived from a reassortment of three avian flu virus strains, and substantial mutations have been detected. Our results highlight the need for systematic surveillance of influenza in birds, and provide evidence that the mixing of new genetic elements in avian can result in the emergence of viruses with pandemic potential in humans.
How well can one jointly measure two incompatible observables on a given quantum state?

Heisenberg’s uncertainty principle is one of the main tenet s of quantum theory. Nevertheless, and despite its fundamental importance for our understanding of quantum fo undations, there has been some confusion in its interpretation: although Heisenberg’s first argument was t h t the measurement of one observable on a quantum state necessarily disturbs another incompatible observab l , standard uncertainty relations typically bound the indeterminacy of the outcomes when either one or the other ob servable is measured. In this paper, we quantify precisely Heisenberg’s intuition. Even if two incompatibl e observables cannot be measured together, one can still approximate their joint measurement, at the price of i ntroducing some errors with respect to the ideal measurement of each of them. We present a new, tight relation characterizing the optimal trade-off between the error on one observable versus the error on the other. As a particular case, our approach allows us to characterize the disturbance of an observable induced by th e approximate measurement of another one; we also derive a stronger error-disturbance relation for this scen ario.
THE ASSEMBLY OF MILKY-WAY-LIKE GALAXIES SINCE z ∼ 2.5

Galaxies with the mass of the Milky Way dominate the stellar mass density of the universe but it is uncertain how and when they were assembled. Here we study progenitors of these galaxies out to z = 2.5, using data from the 3D-HST and CANDELS Treasury surveys. We find that galaxies with present-day stellar masses of log (M) ≈ 10.7 built ∼90% of their stellar mass since z = 2.5, with most of the star formation occurring before z = 1. In marked contrast to the assembly history of massive elliptical galaxies, mass growth is not limited to large radii: the mass in the central 2 kpc of the galaxies increased by a factor of between z = 2.5 and z = 1. We therefore rule out simple models in which bulges were fully assembled at high redshift and disks gradually formed around them. Instead, bulges (and black holes) likely formed in lockstep with disks, through bar instabilities, migration, or other processes. We find that after z = 1 the growth in the central regions gradually stopped and the disk continued to be built up, consistent with recent studies of the gas distributions in z ∼ 1 galaxies and the properties of many spiral galaxies today.
Characterization of Delay Propagation in the US Air-Transportation Network

Complex networks provide a suitable framework to characterize air traffic. Previous works described the world air-transport network as a graph where direct flights are edges and commercial airports are vertices. In this work, we focus instead on the properties of flight delays in the US air- transportation network. We analyze flight performance data in 2010 and study the topological structure of the network as well as the aircraft rotation. The properties of flight delays, including the distribution of total delays, the dependence on the day of the week and the hour-by-hour evolution within each day, are characterized with special attention to flights accumulating delays longer than 12 hours. We find that the distributions are robust to changes in takeoff or landing operations, different moments of the year, or even different airports in the contiguous states. However, airports in remote areas (Hawaii, Alaska, Puerto Rico) can show peculiar distributions biased toward long delays. Additionally, we show that long-delayed flights have an important dependence on the destination airport.
Osteology of a Near-Complete Skeleton of Tenontosaurus tilletti (Dinosauria: Ornithopoda) from the Cloverly Formation, Montana, USA

The character diagnosis of Tenontosaurus tilletti has been revised and redefined into a more robust and quantifiable state. Significant emphasis is placed on constructing phylogenetic definition in such a method, as it prevents occlusion of true character states by alleviating potential individual interpretational bias. Previous placement within the Iguanodontia is refuted based on the lack of character affinity with the defining synapomorphies of the clade. The clade Hypsilophodontidae (=Hypsilophodontia), along with Iguanodontia, however is deemed to be in critical need of refinement to account for recent discoveries and re-classifications of certain euornithopods. Several of the synapomorphies are out-dated and deemed redundant in favour of a more quantifiable approach. Re- definition of these clades is critical if the current state of basal euornithopodan relationships is to be resolved. Phylogenetic studies must be approached from a multidisciplinary perspective; integration of tectonostratigraphical, ontogenetic, palaeoecological, and biomechanical data with sets of well-defined primary homologies are essential in increasing phylogenetic resolution and generating stratigraphically feasible ancestor-descendant relationships. Material attributed to Tenontosaurus tilletti is in need of strict re-analysis; the significant quantity of specimens attributed to this species is potentially the result of poor stratigraphic constraints and the vast spatiotemporal span occupied. Future revision of this material is expected to reveal temporal variations on the species -level inherently linked to environmental evolution, as well as possibly provide clues to sexual dimorphism in contemporaneous, yet morphologically distinct tenontosaurs.
Clusters of microRNAs emerge by new hairpins in existing transcripts

Genetic linkage may result in the expression of multiple products from a polycistronic transcript, under the control of a single promoter. In animals, protein-coding polycistronic transcripts are rare. However, microRNAs are frequently clustered in the genomes of animals, and these clusters are often transcribed as a single unit. The evolution of microRNA clusters has been the subject of much speculation, and a selective advantage of clusters of functionally related microRNAs is often proposed. However, the origin of microRNA clusters has not been so far explored. Here, we study the evolution of microRNA clusters in Drosophila melanogaster. We observed that the majority of microRNA clusters arose by the de novo formation of new microRNA-like hairpins in existing microRNA transcripts. Some clusters also emerged by tandem duplication of a single microRNA. Comparative genomics show that these clusters are unlikely to split or undergo rearrangements. We did not find any instances of clusters appearing by rearrangement of pre-existing microRNA genes. We propose a model for microRNA cluster evolution in which selection over one of the microRNAs in the cluster interferes with the evolution of the other linked microRNAs. Our analysis suggests that the study of microRNAs and small RNAs must consider linkage associations.
Dempster-Shafer vs. Probabilistic Logic

The combination of evidence in Dempster-Shafer theory is compared with the combination of evidence in probabilistic logic. Sufficient conditions are stated for these two methods to agree. It is then shown that these conditions are minimal in the sense that disagreement can occur when any one of them is removed. An example is given in which the traditional assumption of conditional independence of evidence on hypotheses holds and a uniform prior is assumed, but probabilistic logic and Dempster's rule give radically different results for the combination of two evidence events.
Higher order probabilities

A number of writers have supposed that for the full specification of belief, higher order probabilities are required. Some have even supposed that there may be an unending sequence of higher order probabilities of probabilities of probabilities. ... In the present paper we show that higher order probabilities can always be replaced by the marginal distributions of joint probability distributions. We consider both the case in which higher order probabilities are of the same sort as lower order probabilities and that in which higher order probabilities are distinct in character, as when lower order probabilities are construed as frequencies and higher order probabilities are construed as subjective degrees of belief. In neither case do higher order probabilities appear to offer any advantages, either conceptually or computationally.
Neutron-capture element deficiency of the Hercules dwarf spheroidal galaxy

We present an assessment of the barium abundance ratios for red giant member stars in the faint Hercules dwarf spheroidal (dSph) galaxy. Our results are drawn from intermediate-resolution FLAMES/GIRAFFE spectra around the Ba II 6141.71 angstrom absorption line at low signal-to-noise ratios. For three brighter stars we were able to gain estimates from direct equivalent-width measurements, while for the remaining eight stars only upper limits could be obtained. These results are investigated in a statistical manner and indicate very low Ba abundances of log epsilon(Ba) less than or similar to 0.7 dex (3 sigma). We discuss various possible systematic biasses, first and foremost, a blend with the Fe I 6141.73 angstrom-line, but most of those would only lead to even lower abundances. A better match with metal-poor halo and dSph stars can only be reached by including a large uncertainty in the continuum placement. This contrasts with the high dispersions in iron and calcium (in excess of 1 dex) in this galaxy. While the latter spreads are typical of the very low luminosity, dark-matter dominated dSphs, a high level of depletion in heavy elements suggests that chemical enrichment in Hercules was governed by very massive stars, coupled with a very low star formation efficiency. While very low abundances of some heavy elements are also found in individual stars of other dwarf galaxies, this is the first time that a very low Ba abundance is found within an entire dSph over a broad metallicity range.
The EMC Effect and High Momentum Nucleons in Nuclei

Recent developments in understanding the influence of the nucleus on deep-inelastic structure functions, the EMC effect, are reviewed. A new data base which expresses ratios of structure functions in terms of the Bjorken variable xA = AQ2/(2MA q0) is presented. Information about two-nucleon short-range correlations (SRC) from experiments is also discussed and the remarkable linear relation between SRC and the EMC effect is reviewed. A convolution model that relates the underlying source of the EMC effect to modification of either the mean-field nucleons or SRC nucleons is presented. It is shown that both approaches are equally successful in describing the current EMC data.
How stable is the photon?

Yes, the photon. While a nonzero photon mass has been under experimental and theoretical study for years, the possible implication of a finite photon lifetime lacks discussion. The tight experimental upper bound of the photon mass restricts the kinematically allowed final states of photon decay to the lightest neutrino and/or particles beyond the standard model. We discuss the modifications of the well-measured cosmic microwave background spectrum of free streaming photons due to photon mass and lifetime and obtain model-independent constraints on both parameters--most importantly a lower direct bound of 3 yr on the photon lifetime, should the photon mass be at its conservative upper limit. In that case, the lifetime of microwave photons will be time-dilated by a factor order 10(15).
Planck 2013 results support the cyclic universe

We show that results from the Planck satellite reported in 2013 are consistent with cyclic models of the Universe for natural parameter ranges (i.e. order unity dimensionless coefficients), assuming the standard entropic mechanism for generating curvature perturbations. With improved precision, forthcoming results from Planck and other experiments should be able to test the remaining parameter range and confirm or refute the core predictions, i.e. no observable primordial $B$-mode polarization and detectable local non-Gaussianity. A new prediction, given the Planck 2013 constraints on the bispectrum, is a sharp constraint on the local trispectrum parameter ${g}_{NL}$; namely, the currently best-understood models predict it is negative, with ${g}_{NL}\ensuremath{\lesssim}\ensuremath{-}1700$.
Rare Decays of $K$ and $B$ Mesons Revisited

The rare decays of mesons are higher order effects in weak interactions. The main contributions to such decay processes are from the Z-penguin, the photonpenguin and the box diagram. At the quark level, these contributions are well known. However, when considering the corresponding physical hadronic processes, a knowledge of how hadronic states are expressed in terms of quarks. In this paper, we suggest a simplistic way to relate the quark level process to the hadronic process. For simplicity, we consider here only the decays of pseudoscalar mesons. The meson-quark coupling is described in terms of a gamma-5 coupling with a constant coupling constant. We apply the model to processes in which meson M1 decays to meson M2 with the emissions of neutrino pair and charged lepton pair. In calculating the decay rates, a cut-off momentum lamda is introduced to control the divergent triangle integral over the internal momentum. The results of our calculation is compared to experimental data on the decay rates for K- and B-meson decays.
Cloud Computing Research Challenges

In recent times cloud computing has appeared as a new model for hosting and conveying services over the Internet. This model is striking to business vendors as it eradicates the requirement for users to plan in advance, and it permits the organization to start from low level and then add more resources only if there is an increase in the service demand. Even though cloud computing presents greater opportunities not only to information technology industry, but every organization involved in utilizing the computing in one way or the other, it is still in infancy with many problems to be fixed. The paper discusses research challenges in cloud computing.