cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Singular integrals and a problem on mixing flows
Creators: name: Hadžić, Mahir
name: Seeger, Andreas
name: Smart, Charles K.
name: Street, Brian
Publisher: name: arXiv
Year: 2016
Subjects: subject: Classical Analysis and ODEs (math.CA)
subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics
subject: 34C11, 35Q35, 37C10, 42B20

description: We prove a result related to Bressan's mixing problem. We establish an inequality for the change of Bianchini semi-norms of characteristic functions under the flow generated by a divergence free time dependent vector field. The approach leads to a bilinear singular integral operator for which we prove bounds on Hardy spaces. We include additional observations about the approach and a discrete toy version of Bressan's problem.
description: To appear in Annales de l'Institut Henri Poincar\'e (C) Analyse Non Lin\'eaire
Noncollinear magnetic ordering in the Shastry-Sutherland Kondo lattice model: Insulating regime and the role of Dzyaloshinskii-Moriya interaction
Creators: name: Shahzad, Munir
name: Sengupta, Pinaki
Publisher: name: arXiv
Year: 2017
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We investigate the necessary conditions for the emergence of complex, noncoplanar magnetic configurations in a Kondo lattice model with classical local moments on the geometrically frustrated Shastry-Sutherland lattice and their evolution in an external magnetic field. We demonstrate that topologically nontrivial spin textures, including a new canted flux state, with nonzero scalar chirality arise dynamically from realistic short-range interactions. Our results establish that a finite Dzyaloshinskii-Moriya (DM) interaction is necessary for the emergence of these novel magnetic states when the system is at half filling, for which the ground state is insulating. We identify the minimal set of DM vectors that are necessary for the stabilization of chiral magnetic phases. The noncoplanarity of such structures can be tuned continually by applying an external magnetic field. This is the first part in a series of two papers; in the following paper the effects of frustration, thermal fluctuations, and magnetic field on the emergence of novel noncollinear states at metallic filling of itinerant electrons are discussed. Our results are crucial in understanding the magnetic and electronic properties of the rare-earth tetraboride family of frustrated magnets with separate spin and charge degrees of freedom.
description: 8 pages, 5 figures
Examples of reflection positive Euclidean field theories
Creators: name: Trinchero, Roberto
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The requirement of reflection positivity(RP) for Euclidean field theories is considered. This is done for the cases of a scalar field, a higher derivative scalar field theory and the scalar field theory defined on a non-integer dimensional space(NIDS). It is shown that regarding RP, the analytical structure of the corresponding Schwinger functions plays an important role. For the higher derivative scalar field theory RP does not hold. However for the scalar field theory on a NIDS, RP holds in a certain range of dimensions where the corresponding Minkowskian field is defined on a Hilbert space with a positive definite scalar product that provides a unitary representation of the Poincaré group. In addition, and motivated by the last example, it is shown that, under certain conditions, one can construct non-local reflection positive Euclidean field theories starting from the corrected two point functions of interacting local field theories.
description: 14 pages, no figures, changes in various proofs
Range Assignment of Base-Stations Maximizing Coverage Area without Interference
Creators: name: Acharyya, Ankush
name: De, Minati
name: Nandy, Subhas C.
name: Roy, Bodhayan
Publisher: name: arXiv
Year: 2017
Subjects: subject: Computational Geometry (cs.CG)
subject: FOS: Computer and information sciences
subject: 52C15, 52C17

description: We study the problem of assigning non-overlapping geometric objects centered at a given set of points such that the sum of area covered by them is maximized. If the points are placed on a straight-line and the objects are disks, then the problem is solvable in polynomial time. However, we show that the problem is NP-hard even for simplest objects like disks or squares in ${\mathbb{R}}^2$. Eppstein [CCCG, pages 260--265, 2016] proposed a polynomial time algorithm for maximizing the sum of radii (or perimeter) of non-overlapping balls or disks when the points are arbitrarily placed on a plane. We show that Eppstein's algorithm for maximizing sum of perimeter of the disks in ${\mathbb{R}}^2$ gives a $2$-approximation solution for the sum of area maximization problem. We propose a PTAS for our problem. These approximation results are extendible to higher dimensions. All these approximation results hold for the area maximization problem by regular convex polygons with even number of edges centered at the given points.
description: 27 pages, 15 figures
The signed enhanced principal rank characteristic sequence
Creators: name: Martínez-Rivera, Xavier
Publisher: name: arXiv
Year: 2016
Subjects: subject: Combinatorics (math.CO)
subject: FOS: Mathematics

description: The signed enhanced principal rank characteristic sequence (sepr-sequence) of an $n \times n$ Hermitian matrix is the sequence $t_1t_2 \cdots t_n$, where $t_k$ is either $\tt A^*$, $\tt A^+$, $\tt A^-$, $\tt N$, $\tt S^*$, $\tt S^+$, or $\tt S^-$ based on the following criteria: $t_k = \tt A^*$ if $B$ has both a positive and a negative order-$k$ principal minor, and each order-$k$ principal minor is nonzero. $t_k = \tt A^+$ (respectively, $t_k = \tt A^-$) if each order-$k$ principal minor is positive (respectively, negative). $t_k = \tt N$ if each order-$k$ principal minor is zero. $t_k = \tt S^*$ if $B$ has each a positive, a negative, and a zero order-$k$ principal minor. $t_k = \tt S^+$ (respectively, $t_k = \tt S^-$) if $B$ has both a zero and a nonzero order-$k$ principal minor, and each nonzero order-$k$ principal minor is positive (respectively, negative). Such sequences provide more information than the $({\tt A,N,S})$ epr-sequence in the literature, where the $k$th term is either $\tt A$, $\tt N$, or $\tt S$ based on whether all, none, or some (but not all) of the order-$k$ principal minors of the matrix are nonzero. Various sepr-sequences are shown to be unattainable by Hermitian matrices. In particular, by applying Muir's law of extensible minors, it is shown that subsequences such as $\tt A^*N$ and $\tt NA^*$ are prohibited in the sepr-sequence of a Hermitian matrix. For Hermitian matrices of orders $n=1,2,3$, all attainable sepr-sequences are classified. For real symmetric matrices, a complete characterization of the attainable sepr-sequences whose underlying epr-sequence contains $\tt ANA$ as a non-terminal subsequence is established.
description: 21 pages. The Version of Record of this manuscript has been published, and is available in Linear and Multilinear Algebra (since August 17, 2017) at http://dx.doi.org/10.1080/03081087.2017.1363149
Noncollinear magnetic ordering in a frustrated magnet: Metallic regime and the role of frustration
Creators: name: Shahzad, Munir
name: Sengupta, Pinaki
Publisher: name: arXiv
Year: 2017
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We explore the magnetic phases in a Kondo lattice model on the geometrically frustrated Shastry-Sutherland lattice at metallic electron densities, searching for noncollinear and noncoplanar spin textures. Motivated by experimental observations in many rare-earth-based frustrated metallic magnets, we treat the local moments as classical spins and set the coupling between the itinerant electrons and local moments as the largest energy scale in the problem. Our results show that a noncollinear flux state is stabilized over an extended range of Hamiltonian parameters. These spin states can be quenched efficiently by external fields like temperature and magnetic field as well as by varying the degree of frustration in the electronic itinerancy and exchange coupling between local moments. Interestingly, unlike insulating electron densities that we discussed in paper I of this sequence, a Dzyaloshinskii-Moriya interaction between the local moments is not essential for the emergence of their noncollinear ordering.
description: 8 pages, 8 figures
The pitfalls of planar spin-glass benchmarks: Raising the bar for quantum annealers (again)
Creators: name: Mandrà, Salvatore
name: Katzgraber, Helmut G.
name: Thomas, Creighton
Publisher: name: arXiv
Year: 2017
Subjects: subject: Quantum Physics (quant-ph)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: FOS: Physical sciences

description: In an effort to overcome the limitations of random spin-glass benchmarks for quantum annealers, focus has shifted to carefully-crafted gadget-based problems whose logical structure has typically a planar topology. Recent experiments on these gadget problems using a commercially-available quantum annealer have demonstrated an impressive performance over a selection of commonly-used classical optimization heuristics. Here we show that efficient classical optimization techniques, such as minimum-weight perfect matching, can solve these gadget problems exactly and in polynomial time. We present approaches on how to mitigate this shortcoming of commonly-used benchmark problems based on planar logical topologies.
description: 5 pages, 2 figures
Modelling ultraviolet-line diagnostics of stars, the ionized and the neutral interstellar medium in star-forming galaxies
Creators: name: Vidal-García, A.
name: Charlot, S.
name: Bruzual, G.
name: Hubeny, I.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We combine state-of-the-art models for the production of stellar radiation and its transfer through the interstellar medium (ISM) to investigate ultraviolet-line diagnostics of stars, the ionized and the neutral ISM in star-forming galaxies. We start by assessing the reliability of our stellar population synthesis modelling by fitting absorption-line indices in the ISM-free ultraviolet spectra of 10 Large-Magellanic-Cloud clusters. In doing so, we find that neglecting stochastic sampling of the stellar initial mass function in these young ($\sim10$-100 Myr), low-mass clusters affects negligibly ultraviolet-based age and metallicity estimates but can lead to significant overestimates of stellar mass. Then, we proceed and develop a simple approach, based on an idealized description of the main features of the ISM, to compute in a physically consistent way the combined influence of nebular emission and interstellar absorption on ultraviolet spectra of star-forming galaxies. Our model accounts for the transfer of radiation through the ionized interiors and outer neutral envelopes of short-lived stellar birth clouds, as well as for radiative transfer through a diffuse intercloud medium. We use this approach to explore the entangled signatures of stars, the ionized and the neutral ISM in ultraviolet spectra of star-forming galaxies. We find that, aside from a few notable exceptions, most standard ultraviolet indices defined in the spectra of ISM-free stellar populations are prone to significant contamination by the ISM, which increases with metallicity. We also identify several nebular-emission and interstellar-absorption features, which stand out as particularly clean tracers of the different phases of the ISM.
description: 27 pages, 21 figures. Accepted for publication in MNRAS
Dimensional lower bounds for Falconer type incidence and point configuration theorems
Creators: name: DeWitt, Jonathan
name: Ford, Kevin
name: Goldstein, Eli
name: Miller, Steven J.
name: Moreland, Gwyneth
name: Palsson, Eyvindur A.
name: Senger, Steven
Publisher: name: arXiv
Year: 2016
Subjects: subject: Classical Analysis and ODEs (math.CA)
subject: Number Theory (math.NT)
subject: FOS: Mathematics
subject: 28A78 (primary), 11D45, 05D05 (secondary)

description: Let $1 \leq k \leq d$ and consider a subset $E\subset \mathbb{R}^d$. In this paper, we study the problem of how large the Hausdorff dimension of $E$ must be in order for the set of distinct noncongruent $k$-simplices in $E$ (that is, noncongruent point configurations of $k+1$ points from $E$) to have positive Lebesgue measure. This generalizes the $k=1$ case, the well-known Falconer distance problem and a major open problem in geometric measure theory. We establish a dimensional lower threshold of $\frac{d(k+1)}{d+2}$ for Falconer type theorems for $k$-simplices. This threshold is nontrivial in the range $d/2 \leq k \leq d$ and is obtained through counting simplices in a standard lattice using results of the Gauss circle problem. Many results on Falconer type theorems have been established through incidence theorems, which generally establish sufficient but not necessary conditions for the point configuration theorems. We also establish a dimensional lower threshold of $\frac{d+1}{2}$ on incidence theorems for $k$-simplices where $k\leq d \leq 2k+1$ by generalizing an example of Mattila. Finally, we prove a dimensional lower threshold of $\frac{d+1}{2}$ on incidence theorems for triangles in a convex setting in every dimension greater than $3$. This last result generalizes work by Iosevich and Senger on distances that was built on a construction by Valtr. The final result utilizes number-theoretic machinery to estimate the number of solutions to a Diophantine equation.
description: 10 pages, 1 figure. Main focus of the paper made clearer and more details given
Counting Quasi-Idempotent Irreducible Integral Matrices
Creators: name: Thörnblad, Erik
name: Zimmermann, Jakob
Publisher: name: arXiv
Year: 2017
Subjects: subject: Combinatorics (math.CO)
subject: Representation Theory (math.RT)
subject: FOS: Mathematics

description: Given any polynomial $p$ in $C[X]$, we show that the set of irreducible matrices satisfying $p(A)=0$ is finite. In the specific case $p(X)=X^2-nX$, we count the number of irreducible matrices in this set and analyze the arising sequences and their asymptotics. Such matrices turn out to be related to generalized compositions and generalized partitions.
description: 11 pages
The Stochastic complexity of spin models: Are pairwise models really simple?
Creators: name: Beretta, Alberto
name: Battistin, Claudia
name: de Mulatier, Clélia
name: Mastromatteo, Iacopo
name: Marsili, Matteo
Publisher: name: arXiv
Year: 2017
Subjects: subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Machine Learning (stat.ML)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences

description: Models can be simple for different reasons: because they yield a simple and computationally efficient interpretation of a generic dataset (e.g. in terms of pairwise dependences) - as in statistical learning - or because they capture the essential ingredients of a specific phenomenon - as e.g. in physics - leading to non-trivial falsifiable predictions. In information theory and Bayesian inference, the simplicity of a model is precisely quantified in the stochastic complexity, which measures the number of bits needed to encode its parameters. In order to understand how simple models look like, we study the stochastic complexity of spin models with interactions of arbitrary order. We highlight the existence of invariances with respect to bijections within the space of operators, which allow us to partition the space of all models into equivalence classes, in which models share the same complexity. We thus found that the complexity (or simplicity) of a model is not determined by the order of the interactions, but rather by their mutual arrangements. Models where statistical dependencies are localized on non-overlapping groups of few variables (and that afford predictions on independencies that are easy to falsify) are simple. On the contrary, fully connected pairwise models, which are often used in statistical learning, appear to be highly complex, because of their extended set of interactions.
Quantum backflow and scattering
Creators: name: Bostelmann, Henning
name: Cadamuro, Daniela
name: Lechner, Gandalf
Publisher: name: arXiv
Year: 2017
Subjects: subject: Quantum Physics (quant-ph)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences
subject: 81U99 (Primary), 81-04, 47G10 (Secondary)

description: Backflow is the phenomenon that the probability current of a quantum particle on the line can flow in the direction opposite to its momentum. In this article, previous investigations of backflow, pertaining to interaction-free dynamics or purely kinematical aspects, are extended to scattering situations in short-range potentials. It is shown that backflow is a universal quantum effect which exists in any such potential, and is always of bounded spatial extent in a specific sense. The effects of reflection and transmission processes on backflow are investigated, both analytically for general potentials, and numerically in various concrete examples.
description: minor changes, as published in Phys. Rev. A; 13 pages, 11 figures, 3 videos, computer code
On skew braces (with an appendix by N. Byott and L. Vendramin)
Creators: name: Smoktunowicz, A.
name: Vendramin, L.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Group Theory (math.GR)
subject: Quantum Algebra (math.QA)
subject: FOS: Mathematics
subject: 16T25, 81R50

description: Braces are generalizations of radical rings, introduced by Rump to study involutive non-degenerate set-theoretical solutions of the Yang-Baxter equation (YBE). Skew braces were also recently introduced as a tool to study not necessarily involutive solutions. Roughly speaking, skew braces provide group-theoretical and ring-theoretical methods to understand solutions of the YBE. It turns out that skew braces appear in many different contexts, such as near-rings, matched pairs of groups, triply factorized groups, bijective 1-cocycles and Hopf-Galois extensions. These connections and some of their consequences are explored in this paper. We produce several new families of solutions related in many different ways with rings, near-rings and groups. We also study the solutions of the YBE that skew braces naturally produce. We prove, for example, that the order of the canonical solution associated with a finite skew brace is even: it is two times the exponent of the additive group modulo its center.
description: 37 pages. Final version
Comprehensiveness and Instructional Quality of YouTube Videos on Clinical Record-Keeping Training in Medical Education
Creators: name: Emekli, Emre
name: Kıyak, Yavuz Selim
Publisher: name: figshare
Year: 2024
Subjects: classificationCode: 390303
subject: Higher education

description: The article titled "Comprehensiveness and Instructional Quality of YouTube Videos on Clinical Record-Keeping Training in Medical Education" provides a detailed examination of YouTube videos as educational tools for medical students and professionals, focusing on clinical record-keeping. The study highlights the importance of clinical records in healthcare and points out the lack of sufficient education in this area, which has led students and professionals to turn to online resources like YouTube for guidance.The authors conducted a descriptive study, where they searched for relevant videos on YouTube using specific keywords related to clinical record-keeping. From an initial pool of 1298 videos, 59 met the eligibility criteria and were included in the analysis. These videos were evaluated for comprehensiveness using established tools such as the QNOTE instrument and a checklist for progress notes. The instructional quality of the videos was assessed using the Instructional Video Quality Checklist (IVQC).The study's results showed that the average comprehensiveness score was 60.4 out of 100, indicating that many videos did not fully cover the necessary components of clinical record-keeping. The instructional quality score was also low, with an average of 11.19 out of 27. Videos uploaded by universities, professional organizations, or individual academics tended to have higher instructional quality but still lacked in comprehensiveness.The authors discuss the implications of these findings, emphasizing the need for medical educators to guide students toward reliable educational materials and to improve the quality of online content. They also suggest that creating high-quality, comprehensive instructional videos can help bridge the gap in clinical record-keeping education.The study concludes that while YouTube can be a valuable resource, its educational content should be used cautiously, and efforts should be made to enhance the quality and comprehensiveness of such materials.
A Markovian Model of the Evolving World Input-Output Network
Creators: name: Moosavi, Vahid
name: Isacchini, Giulio
Publisher: name: arXiv
Year: 2016
Subjects: subject: General Economics (econ.GN)
subject: Social and Information Networks (cs.SI)
subject: Physics and Society (physics.soc-ph)
subject: General Finance (q-fin.GN)
subject: FOS: Economics and business
subject: FOS: Computer and information sciences
subject: FOS: Physical sciences

description: The initial theoretical connections between Leontief input-output models and Markov chains were established back in 1950s. However, considering the wide variety of mathematical properties of Markov chains, there has not been a full investigation of evolving world economic networks with Markov chain formalism. Using the recently available world input-output database, we modeled the evolution of the world economic network from 1995 to 2011 through analysis of a series of finite Markov chains. We assessed different aspects of this evolving system via different properties of the Markov chains such as mixing time, Kemeny constant, steady state probabilities and perturbation analysis of the transition matrices. First, we showed how the time series of mixing times and Kemeny constants could be used as an aggregate index of globalization. Next, we focused on the steady state probabilities as a measure of structural power of the economies that are comparable to GDP shares of economies as the traditional index of economies. Further, we introduced two measures of systemic risk, called systemic influence and systemic fragility, where the former is the ratio of number of influenced nodes to the total number of nodes, caused by a shock in the activity of a node and the latter is based on the number of times a specific economic node is affected by a shock in the activity of any of the other nodes. Finally, focusing on Kemeny constant as a global indicator of monetary flow across the network, we showed that there is a paradoxical effect of a change in activity levels of economic nodes on the overall flow of the network. While the economic slowdown of the majority of nodes with high structural power results to a slower average monetary flow over the network, there are some nodes, where their slowdowns improve the overall quality of the network in terms of connectivity and the average monetary flow.
title: Die rechtlichen Probleme der Unterscheidung von Arbeitern und Angestellten im Bereich der Versicherungsfälle der geminderten Arbeitsfähigkeit
Creators: name: Bulla-Wagner, Barbara
Year: 2022

description: Die Unterscheidung von Arbeitern und Angestellten ist in der österreichischen Arbeitswelt nach wie vor ein vertrautes Bild, die auch in der gesetzlichen Pensionsversicherung ihren Niederschlag findet. Das Leistungsrecht der Pensionsversicherung sieht für den Fall eines gesundheitsbedingten Abfallens bzw. Ausfalls der Arbeitsfähigkeit eine Geldleistung vor, die als Ersatz für das wegfallende Entgelt den Lebensunterhalt sichern soll, wobei diese gesundheitliche Einschränkung ein gewisses Ausmaß erreicht haben muss. Der Gesetzgeber hat bei der Normierung des Versicherungsfalles der geminderten Arbeitsfähigkeit bewusst alternative Formen und damit Leistungsvoraussetzungen in Abhängigkeit von der Zugehörigkeit eines Versicherten zu einem Versicherungszweig geschaffen. Das dem „Invaliditätsrecht“ zugrundeliegende Berufsschutzsystem bevorzugt aufgrund seiner Ausgestaltung die qualifizierten Arbeitnehmer, hingegen haben unqualifizierte, oftmals körperlich stark beanspruchte Versicherte, einen erschwerten Zugang zu den Leistungen der gesetzlichen Pensionsversicherung. Der Berufsschutz stellt - entsprechend seiner Bezeichnung - einen Schutz vor Verweisung auf andere Berufe dar, wenn der bisherige Beruf vom Versicherten aus gesundheitlichen Gründen nicht weiter ausgeübt werden kann. Dies führt im Ergebnis dazu, dass unqualifizierte Versicherte mit einem Verweisungsfeld konfrontiert werden, das nahezu mit dem gesamten Arbeitsmarkt ident ist. Anhand einer Darstellung der seitens der Judikatur entwickelten Grundsätze zur Zulässigkeit und Zumutbarkeit einer Verweisung können auch die im Tatsächlichen bestehenden Unterschiede aufgezeigt werden. Dies wirft folglich die Frage nach der Sachlichkeit im Hinblick auf Art 7 B-VG auf, zumal der Gleichheitssatz auch den Gesetzgeber bindet und dieser die Differenzierungen in den Bestimmungen über den Versicherungsfall der geminderten Arbeitsfähigkeit im Zuge zahlreicher Novellen entschärft, jedoch nicht gänzlich aufgegeben hat. Der VfGH hat sich bereits mit dieser Ungleichbehandlung befasst, doch lässt sich aus der dazu entwickelten Ordnungssystemjudikatur wenig gewinnen und bedarf es daher eines Blickes über die nationalen Grenzen, um einerseits den Weg des deutschen Gesetzgebers zur Abkehr vom Berufsschutzsystem zu skizzieren und um andererseits gänzlich andere Zugänge im Umgang mit Invalidität zu veranschaulichen. Der österreichische Gesetzgeber hat unter Mitwirkung profunder Kenner der Materie mehrere Lösungsvorschläge zur Neugestaltung des „Invaliditätsrechts“ erarbeiten lassen, auf eine Umsetzung darf gewartet werden.
On universal features of the turbulent cascade in terms of non-equilibrium thermodynamics
Creators: name: Reinke, Nico
name: Fuchs, Andre
name: Nickelsen, Daniel
name: Peinke, Joachim
Publisher: name: arXiv
Year: 2017
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: Features of the turbulent cascade are investigated for various datasets from three different turbulent flows. The analysis is focused on the question as to whether developed turbulent flows show universal small scale features. To answer this question, 2-point statistics and joint multi-scale statistics of longitudinal velocity increments are analysed. Evidence of the Markov property for the turbulent cascade is shown, which corresponds to a 3-point closure that reduces the joint multi-scale statistics to simple conditional probability density functions (cPDF). The cPDF are described by the Fokker-Planck equation in scale and its Kramers-Moyal coefficients (KMCs). KMCs are obtained by a self-consistent optimisation procedure from the measured data and result in a Fokker-Planck equation for each dataset. The knowledge of these stochastic cascade equations enables to make use of the concepts of non-equilibrium thermodynamics and thus to determine the entropy production along individual cascade trajectories. In addition to this new concept, it is shown that the local entropy production is nearly perfectly balanced for all datasets by the integral fluctuation theorem (IFT). Thus the validity of the IFT can be taken as a new law of the turbulent cascade and at the same time independently confirms that the physics of the turbulent cascade is a memoryless Markov process in scale. IFT is taken as a new tool to prove the optimal functional form of the Fokker-Planck equations and subsequently to investigate the question of universality of small scale turbulence. The results of our analysis show that the turbulent cascade contains universal and non-universal features. We identify small scale intermittency as a universality breaking feature. We conclude that specific turbulent flows have their own particular multi-scale cascade, with other words their own stochastic fingerprint.
description: 37 pages, 53 figures, majorly revised
Speed trajectory planning at signalized intersections using sequential convex optimization
Creators: name: Huang, Xianan
name: Peng, Huei
Publisher: name: arXiv
Year: 2017
Subjects: subject: Optimization and Control (math.OC)
subject: FOS: Mathematics

description: An algorithm is developed to optimize vehicle speed trajectory over multiple signalized intersections with known traffic signal information to minimize fuel consumption and travel time, and to meet ride comfort requirements using sequential convex optimization method. A comparison between the proposed method and dynamic programming is carried out to verify its optimality. In addition, vehicle motion during turning is studied because of its significant effect on fuel consumption and travel time.
description: 2017 American Control Conference, May 24-26, Seattle, WA, USA
The convective surface of the red supergiant Antares. VLTI/PIONIER interferometry in the near infrared
Creators: name: Montargès, M.
name: Chiavassa, A.
name: Kervella, P.
name: Ridgway, S. T.
name: Perrin, G.
name: Bouquin, J. -B. Le
name: Lacour, S.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Context. Convection is a candidate to explain the trigger of red supergiant star mass loss. Owing to the small size of the convective cells on the photosphere, few of their characteristics are known. Aims. Using near infrared interferometry, we intend to resolve the photosphere of red supergiant stars and to bring new constraints on their modeling. Methods. We observed the nearby red supergiant Antares using the 4-telescope instrument VLTI/PIONIER. We collected data on the three available configurations of the 1.8m telescopes in the H band. Results. We obtained unprecedented angular resolution on the disk of a star (6% of the star angular diameter) that limits the mean size of convective cells, brings new constraints on numerical simulations. Using an analytical model with a distribution of bright spots we determine their effect on the visibility signal. Conclusion. We determine that the interferometric signal on Antares is compatible with convective cells with various sizes from 45% to 5% of the angular diameter. We also conclude that convective cells can strongly affect the angular diameter and limb-darkening measurements. In particular, the apparent angular diameter becomes dependent on the sampled position angles.
description: 13 pages, 10 figures. Accepted for publication in Astronomy & Astrophysics. Language editing and typo corrections
Equilibration time scales in closed many-body quantum systems
Creators: name: de Oliveira, Thiago R.
name: Charalambous, Christos
name: Jonathan, Daniel
name: Lewenstein, Maciej
name: Riera, Arnau
Publisher: name: arXiv
Year: 2017
Subjects: subject: Quantum Physics (quant-ph)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We show that the physical mechanism for the equilibration of closed quantum systems is dephasing, and identify the energy scales that determine the equilibration timescale of a given observable. For realistic physical systems (e.g those with local Hamiltonians), our arguments imply timescales that do not increase with the system size, in contrast to previously known upper bounds. In particular we show that, for such Hamiltonians, the matrix representation of local observables in the energy basis is banded, and that this property is crucial in order to derive equilibration times that are non-negligible in macroscopic systems. Finally, we give an intuitive interpretation to recent theorems on equilibration time-scale.
description: published version (small changes to improve the text, introduction shortened)
Collision of Two Rotating Hayward Black Holes
Creators: name: Gwak, Bogeun
Publisher: name: arXiv
Year: 2017
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We investigate the spin interaction and the gravitational radiation thermally allowed in a head-on collision of two rotating Hayward black holes. The Hayward black hole is a regular black hole in a modified Einstein equation, and hence it can be an appropriate model to describe the extent to which the regularity effect in the near-horizon region affects the interaction and the radiation. If one black hole is assumed to be considerably smaller than the other, the potential of the spin interaction can be analytically obtained and is dependent on the alignment of angular momenta of the black holes. For the collision of massive black holes, the gravitational radiation is numerically obtained as the upper bound by using the laws of thermodynamics. The effect of the Hayward black hole tends to increase the radiation energy, but we can limit the effect by comparing the radiation energy with the gravitational waves GW150914 and GW151226.
description: 25 pages, 43 figures, published version in EPJC
Primordial perturbations generated by Higgs field and $R^2$ operator
Creators: name: Wang, Yun-Chao
name: Wang, Tower
Publisher: name: arXiv
Year: 2017
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: If the very early Universe is dominated by the non-minimally coupled Higgs field and Starobinsky's curvature-squared term together, the potential diagram would mimic the landscape of a valley, serving as a cosmological attractor. The inflationary dynamics along this valley is studied, model parameters are constrained against observational data, and the isocurvature perturbation is evaluated.
description: 14 pages, 5 figures, $\rho$-field redefined, Sect V and appendices enlarged
The Role of Tire Leachate in Condition-specific Competition and the Persistence of a Resident Mosquito from a Competitively Superior Invader
Creators: name: Villena, Oswaldo C.
name: Sullivan, Joseph H.
name: Landa, Edward R.
name: Yarwood, Stephanie A.
name: Torrents, Alba
name: Zhang, Aijun
name: Leisnham, Paul T.
Publisher: name: MDPI
Year: 2022
Subjects: Aedes albopictus
Culex pipiens
invasive species
oviposition behavior
tire contaminants
ultraviolet radiation

description: Partial funding for Open Access provided by the UMD Libraries' Open Access Publishing Fund.
description: (1) Background: Condition-specific competition, when the outcome of competition varies with abiotic conditions, can facilitate species coexistence in spatially or temporally variable environments. Discarded vehicle tires degrade to leach contaminants into collected rainwater that provide habitats for competing mosquito species. We tested the hypothesis that more highly degraded tires that contain greater tire leachate alters interspecific mosquito competition to produce a conditionspecific advantage for the resident, Culex pipiens, by altering the outcome of competition with the competitively superior invasive Aedes albopictus. (2) Methods: In a competition trial, varying densities of newly hatched Ae. albopictus and Cx. pipiens larvae were added to tires that had been exposed to three different ultraviolet (UV)-B conditions that mimicked full-sun, shade, or no UV-B conditions in the field. We also measured Cx. pipiens and Ae. albopictus oviposition preference among four treatments with varying tire leachate (high and low) and resources (high and low) amounts to determine if adult gravid females avoided habitats with higher tire leachate. (3) Results: We found stronger competitive effects of Cx. pipiens on the population performance and survival of Ae. albopictus in tires exposed to shade and full-sun conditions that had higher concentrations of contaminants. Further, zinc concentration was higher in emergent adults of Ae. albopictus than Cx. pipiens. Oviposition by these species was similar between tire leachate treatments but not by resource amount. (4) Conclusions: These results suggest that degraded tires with higher tire leachate may promote condition-specific competition by reducing the competitive advantage of invasive Ae. albopictus over resident Cx. pipiens and, combined with Cx. pipiens’ preferential oviposition in higher resource sites, contribute to the persistence of the resident species.
Phonon Bottleneck Identification in Disordered Nanoporous Materials
Creators: name: Romano, Giuseppe
name: Grossman, Jeffrey C.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Nanoporous materials are a promising platform for thermoelectrics in that they offer high thermal conductivity tunability while preserving good electrical properties, a crucial requirement for high- effciency thermal energy conversion. Understanding the impact of the pore arrangement on thermal transport is pivotal to engineering realistic materials, where pore disorder is unavoidable. Although there has been considerable progress in modeling thermal size effects in nanostructures, it has remained a challenge to screen such materials over a large phase space due to the slow simulation time required for accurate results. We use density functional theory in connection with the Boltzmann transport equation, to perform calculations of thermal conductivity in disordered porous materials. By leveraging graph theory and regressive analysis, we identify the set of pores representing the phonon bottleneck and obtain a descriptor for thermal transport, based on the sum of the pore-pore distances between such pores. This approach provides a simple tool to estimate phonon suppression in realistic porous materials for thermoelectric applications and enhance our understanding of heat transport in disordered materials.
A proximity biotinylation assay with a host protein bait reveals multiple factors modulating enterovirus replication
Creators: name: Moghimi, Seyedehmahsa
name: Viktorova, Ekaterina G.
name: Gabaglio, Samuel
name: Zimina, Anna
name: Budnik, Bogdan
name: Wynn, Bridge G.
name: Sztul, Elizabeth
name: Belov, George A.
Publisher: name: PLoS
Year: 2022

description: Partial funding for Open Access provided by the UMD Libraries' Open Access Publishing Fund.
description: As ultimate parasites, viruses depend on host factors for every step of their life cycle. On the other hand, cells evolved multiple mechanisms of detecting and interfering with viral replication. Yet, our understanding of the complex ensembles of pro- and anti-viral factors is very limited in virtually every virus-cell system. Here we investigated the proteins recruited to the replication organelles of poliovirus, a representative of the genus Enterovirus of the Picornaviridae family. We took advantage of a strict dependence of enterovirus replication on a host protein GBF1, and established a stable cell line expressing a truncated GBF1 fused to APEX2 peroxidase that effectively supported viral replication upon inhibition of the endogenous GBF1. This construct biotinylated multiple host and viral proteins on the replication organelles. Among the viral proteins, the polyprotein cleavage intermediates were overrepresented, suggesting that the GBF1 environment is linked to viral polyprotein processing. The proteomics characterization of biotinylated host proteins identified multiple proteins previously associated with enterovirus replication, as well as more than 200 new factors recruited to the replication organelles. RNA metabolism proteins, many of which normally localize in the nucleus, constituted the largest group, underscoring the massive release of nuclear factors into the cytoplasm of infected cells and their involvement in viral replication. Functional analysis of several newly identified proteins revealed both pro- and anti-viral factors, including a novel component of infection-induced stress granules. Depletion of these proteins similarly affected the replication of diverse enteroviruses indicating broad conservation of the replication mechanisms. Thus, our data significantly expand the knowledge of the composition of enterovirus replication organelles, provide new insights into viral replication, and offer a novel resource for identifying targets for anti-viral interventions.
Self-force correction to geodetic spin precession in Kerr spacetime
Creators: name: Akcay, Sarp
Publisher: name: arXiv
Year: 2017
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We present an expression for the gravitational self-force correction to the geodetic spin precession of a spinning compact object with small, but non-negligible mass in a bound, equatorial orbit around a Kerr black hole. We consider only conservative back-reaction effects due to the mass of the compact object ($m_1$) thus neglecting the effects of its spin $s_1$ on its motion, i.e, we impose $s_1 \ll G m_1^2/c$ and $m_1 \ll m_2$, where $m_2$ is the mass parameter of the background Kerr spacetime. We encapsulate the correction to the spin precession in $ψ$, the ratio of the accumulated spin-precession angle to the total azimuthal angle over one radial orbit in the equatorial plane. Our formulation considers the gauge-invariant $\ord(m_1)$ part of the correction to $ψ$, denoted by $Δψ$, and is a generalization of the results of [Class. Quan. Grav., 34, 084001 (2017)] to Kerr spacetime. Additionally, we compute the zero-eccentricity limit of $Δψ$ and show that this quantity differs from the circular-orbit $Δψ^\text{circ}$ by a gauge-invariant quantity containing the gravitational self-force correction to general relativistic periapsis advance in Kerr spacetime. Our result for $Δψ$ is expressed in a manner that readily accommodates numerical/analytical self-force computations, e.g., in radiation gauge, and paves the way for the computation of a new eccentric-orbit Kerr gauge invariant beyond the generalized redshift.
description: Matches the PRD version modulo style preferences and format
Spatial and temporal overlap of domestic cats (Felis catus) and native urban wildlife
Creators: name: Herrera, Daniel J.
name: Cove, Micahel V.
name: McShea, William J.
name: Decker, Sam
name: Flockhart, D.T. Tyler
name: Moore, Sophie M.
name: Gallo, Travis
Publisher: name: Frontiers Media
Year: 2022
Subjects: occupancy
activity
predation
zoonotic disease
feral cats
management
one health
public health

description: Partial funding for Open Access provided by the UMD Libraries' Open Access Publishing Fund.
description: Free-roaming domestic cats (Felis catus) are known to pose threats to ecosystem health via transmission of zoonotic diseases and predation of native wildlife. Likewise, free-roaming cats are also susceptible to predation or disease transmission from native wildlife. Physical interactions are required for many of these risks to be manifested, necessitating spatial and temporal overlap between cats and wildlife species. Therefore, knowledge of the location and extent of shared habitat and activity periods would benefit management programs. We used data from a 3-year camera trap survey to model species-specific occupancy and identify landscape variables that contribute to the distribution of free-roaming domestic cats and eight native mammal species in Washington, DC. (USA). Our analysis includes five species that are common prey items of domestic cats, and three species that are potential disease vectors or are otherwise known to be a risk to cats. We then predicted the probability of occupancy and estimated the probability of spatial overlap between cats and each native wildlife species at multiple scales. We also used kernel density estimations to calculate temporal overlap between cats and each native wildlife species. Across spatial scales, occupancy for potential disease vector species was generally positively correlated with canopy cover and open water. Prey species were also generally positively correlated with canopy cover, but displayed negative associations with human population density and inconsistent associations with average per capita income. Domestic cat occupancy was negatively correlated with natural habitat characteristics and positively correlated with human population density. Predicted spatial overlap between domestic cats and native wildlife was greatest for potential disease vector species. Temporal overlap was high (>0.50) between cats and all but two native wildlife species, indicating that temporal overlap is probable wherever species overlap spatially. Our findings indicate that the risk to and from domestic cats varies across urban landscapes, but primarily arises from human activities. As such, humans are implicated in the negative outcomes that result from cats interacting with wildlife. Data-driven management to reduce such interactions can aid in cat population management, biodiversity conservation, and public health campaigns.
Solitary wave solutions and their interactions for fully nonlinear water waves with surface tension in the generalized Serre equations
Creators: name: Dutykh, Denys
name: Hoefer, Mark
name: Mitsotakis, Dimitrios
Publisher: name: arXiv
Year: 2017
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: Analysis of PDEs (math.AP)
subject: Pattern Formation and Solitons (nlin.PS)
subject: Classical Physics (physics.class-ph)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: Some effects of surface tension on fully-nonlinear, long, surface water waves are studied by numerical means. The differences between various solitary waves and their interactions in subcritical and supercritical surface tension regimes are presented. Analytical expressions for new peaked travelling wave solutions are presented in the case of critical surface tension. The numerical experiments were performed using a high-accurate finite element method based on smooth cubic splines and the four-stage, classical, explicit Runge-Kutta method of order four.
description: 42 pages, 27 figures, 1 table, 48 references. Other author's papers can be downloaded at http://www.denys-dutykh.com/
Path sampling of recurrent neural networks by incorporating known physics
Creators: name: Tsai, Sun-Ting
name: Fields, Eric
name: Xu, Yijia
name: Kuo, En-Jui
name: Tiwary, Pratyush
Publisher: name: Springer
Year: 2022

description: Partial funding for Open Access provided by the UMD Libraries' Open Access Publishing Fund.
description: Recurrent neural networks have seen widespread use in modeling dynamical systems in varied domains such as weather prediction, text prediction and several others. Often one wishes to supplement the experimentally observed dynamics with prior knowledge or intuition about the system. While the recurrent nature of these networks allows them to model arbitrarily long memories in the time series used in training, it makes it harder to impose prior knowledge or intuition through generic constraints. In this work, we present a path sampling approach based on principle of Maximum Caliber that allows us to include generic thermodynamic or kinetic constraints into recurrent neural networks. We show the method here for a widely used type of recurrent neural network known as long short-term memory network in the context of supplementing time series collected from different application domains. These include classical Molecular Dynamics of a protein and Monte Carlo simulations of an open quantum system continuously losing photons to the environment and displaying Rabi oscillations. Our method can be easily generalized to other generative artificial intelligence models and to generic time series in different areas of physical and social sciences, where one wishes to supplement limited data with intuition or theory based corrections.