cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Anisotropic Satellite Galaxy Quenching: A Unique Signature of Energetic Feedback by Supermassive Black Holes?
Creators: name: Karp, Juliana S. M.
name: Lange, Johannes U.
name: Wechsler, Risa H.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: The quenched fraction of satellite galaxies is aligned with the orientation of the halo's central galaxy, such that on average, satellites form stars at a lower rate along the major axis of the central. This effect, called anisotropic satellite galaxy quenching (ASGQ), has been found in observational data and cosmological simulations. Analyzing the IllustrisTNG simulation, Martín-Navarro et al. (2021) recently argued that ASGQ is caused by anisotropic energetic feedback and constitutes "compelling observational evidence for the role of black holes in regulating galaxy evolution." In this letter, we study the causes of ASGQ in state-of-the-art galaxy formation simulations to evaluate this claim. We show that cosmological simulations predict that on average, satellite galaxies along the major axis of the dark matter halo tend to have been accreted at earlier cosmic times and are hosted by subhalos of larger peak halo masses. As a result, a modulation of the quenched fraction with respect to the major axis of the central galaxy is a natural prediction of hierarchical structure formation. We show that ASGQ is predicted by the UniverseMachine galaxy formation model, a model without anisotropic feedback. Furthermore, we demonstrate that even in the IllustrisTNG simulation, anisotropic satellite accretion properties are the main cause of ASGQ. Ultimately, we argue that ASGQ is not a reliable indicator of supermassive black hole feedback in galaxy formation simulations and, thus, should not be interpreted as such in observational data.
description: 7 pages, 4 figures; Submitted to ApJL; Comments welcome!
Stochastic Sampling for Structural Topology Optimization with Many Load Cases: Density-Based and Ground Structure Approaches
Creators: name: Zhang, Xiaojia
name: de Sturler, Eric
name: Paulino, Glaucio H.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Optimization and Control (math.OC)
subject: FOS: Mathematics
subject: 65K10, 74P05, 49Q10

description: We propose an efficient probabilistic method to solve a deterministic problem -- we present a randomized optimization approach that drastically reduces the enormous computational cost of optimizing designs under many load cases for both continuum and truss topology optimization. Practical structural designs by topology optimization typically involve many load cases, possibly hundreds or more. The optimal design minimizes a, possibly weighted, average of the compliance under each load case (or some other objective). This means that in each optimization step a large finite element problem must be solved for each load case, leading to an enormous computational effort. On the contrary, the proposed randomized optimization method with stochastic sampling requires the solution of only a few (e.g., 5 or 6) finite element problems (large linear systems) per optimization step. Based on simulated annealing, we introduce a damping scheme for the randomized approach. Through numerical examples in two and three dimensions, we demonstrate that the stochastic algorithm drastically reduces computational cost to obtain similar final topologies and results (e.g., compliance) compared with the standard algorithms. The results indicate that the damping scheme is effective and leads to rapid convergence of the proposed algorithm.
A catalog of UGC isolated galaxy pairs with accurate radial velocities
Creators: name: Chamaraux, Pierre
name: Nottale, Laurent
Publisher: name: arXiv
Year: 2016
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: The present paper is devoted to the construction of a catalog of isolated galaxy pairs from the Uppsala Galaxy Catalog (UGC), using accurate radial velocities. The UGC lists 12921 galaxies to declination larger than -2 deg 30 min and is complete to an apparent diameter of 1 arcmin. The criteria used to define the isolated galaxy pairs are the following: 1) Velocity criterion: radial velocity difference between the members lower than 500 km/s; 2) Interdistance criterion: projected distance between the members smaller than 1 Mpc; 3) Reciprocity criterion: each member is the closest galaxy to the other one, which excludes multiplets; 4) Isolation information: the catalog lists the ratio between the projected distance to the closest UGC galaxy (having a velocity difference smaller than 500 km/s) and the pair members interdistance, thus allowing one to choose any isolation criterion (beyond the chosen limit 2.5). In addition, we have accounted for the small diameter bias by searching for CGCG galaxies in the pair environment and used the same isolation criterion. A peculiar investigation has allowed to gather very accurate radial velocities for pair members, from high quality HI and optical measurements (median uncertainty on velocity differences 10 km/s). Our final catalog contains 1005 galaxy pairs. Then we give some global properties of the pair catalog. We display the histograms of the radial velocity differences between the pair members and of their projected interdistances (median 0.29 Mpc). Finally, we provide an estimate of the contamination by cosmological false "pairs", which is about 10 percent up to a velocity difference of 380 km/s, beyond which all pairs are probably false.
description: 28 pages, 7 figures, catalog available in VizieR
Ternary borides Nb$_7$Fe$_3$B$_8$ and Ta$_7$Fe$_3$B$_8$ with Kagome-type iron framework
Creators: name: Zheng, Qiang
name: Gumeniuk, Roman
name: Borrmann, Horst
name: Schnelle, Walter
name: Tsirlin, Alexander A.
name: Rosner, Helge
name: Burkhardt, Ulrich
name: Reissner, Michael
name: Grin, Yuri
name: Leithe-Jasper, Andreas
Publisher: name: arXiv
Year: 2016
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Two new ternary borides $TM$$_7$Fe$_3$B$_8$ ($TM$ = Nb, Ta) were synthesized by high-temperature thermal treatment of samples obtained by arc-melting. This new type of structure with space group $P$6/$mmm$, comprises $TM$ slabs containing isolated planar hexagonal [B$_6$] rings and iron centered $TM$ columns in a Kagome type of arrangement. Chemical bonding analysis in Nb$_7$Fe$_3$B$_8$ by means of the electron localizability approach reveals two-center interactions forming the Kagome net of Fe and embedded B, while weaker multicenter bonding present between this net and Nb atoms. Magnetic susceptibility measurements reveal antiferromagnetic order below $T_N$ = 240 K for Nb$_7$Fe$_3$B$_8$ and $T_N$ =265 K for Ta$_7$Fe$_3$B$_8$. Small remnant magnetization below 0.01 $μ_B$/f.u. is observed in the antiferromagnetic state. The bulk nature of the magnetic transitions was confirmed by the hyperfine splitting of the Mößbauer spectra, the sizable anomalies in the specific heat capacity, and the kinks in the resistivity curves. The high-field paramagnetic susceptibilities fitted by the Curie-Weiss law show effective paramagnetic moments $μ_{eff}$ about 3.1 $μ_B$/Fe in both compounds. The temperature dependence of the electrical resistivity also reveals metallic character of both compounds. Density functional calculations corroborate the metallic behaviour of both compounds and demonstrate the formation of a sizable local magnetic moment on the Fe-sites. They indicate the presence of both antiferro- and ferromagnetic interactions.
description: 11 pages, 11 figures
Testing the black hole "no-hair" hypothesis
Creators: name: Cardoso, Vitor
name: Gualtieri, Leonardo
Publisher: name: arXiv
Year: 2016
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: High Energy Physics - Theory (hep-th)
subject: Classical Physics (physics.class-ph)
subject: FOS: Physical sciences

description: Black holes in General Relativity are very simple objects. This property, that goes under the name of "no-hair," has been refined in the last few decades and admits several versions. The simplicity of black holes makes them ideal testbeds of fundamental physics and of General Relativity itself. Here we discuss the no-hair property of black holes, how it can be measured in the electromagnetic or gravitational window, and what it can possibly tell us about our universe.
description: Commissioned by Classical and Quantum Gravity
eMIC-AntiKP: Estimating minimum inhibitory concentrations of antibiotics towards Klebsiella pneumoniae using deep learning
Creators: name: Nguyen, Hoang
name: Ngo, HH
name: Nguyen-Vo, TH
name: Do, TTT
name: Rahardja, S
name: Nguyen, Binh
Publisher: name: Open Access Te Herenga Waka-Victoria University of Wellington
Year: 2023
Subjects: classificationCode: 4601
subject: Applied computing
classificationCode: 3101
subject: Biochemistry and cell biology
classificationCode: 4903
subject: Numerical and computational mathematics
classificationCode: 4613
subject: Theory of computation
classificationCode: 46
subject: Information and computing sciences

description: Nowadays, antibiotic resistance has become one of the most concerning problems that directly affects the recovery process of patients. For years, numerous efforts have been made to efficiently use antimicrobial drugs with appropriate doses not only to exterminate microbes but also stringently constrain any chances for bacterial evolution. However, choosing proper antibiotics is not a straightforward and time-effective process because well-defined drugs can only be given to patients after determining microbic taxonomy and evaluating minimum inhibitory concentrations (MICs). Besides conventional methods, numerous computer-aided frameworks have been recently developed using computational advances and public data sources of clinical antimicrobial resistance. In this study, we introduce eMIC-AntiKP, a computational framework specifically designed to predict the MIC values of 20 antibiotics towards Klebsiella pneumoniae. Our prediction models were constructed using convolutional neural networks and k-mer counting-based features. The model for cefepime has the most limited performance with a test 1-tier accuracy of 0.49, while the model for ampicillin has the highest performance with a test 1-tier accuracy of 1.00. Most models have satisfactory performance, with test accuracies ranging from about 0.70–0.90. The significance of eMIC-AntiKP is the effective utilization of computing resources to make it a compact and portable tool for most moderately configured computers. We provide users with two options, including an online web server for basic analysis and an offline package for deeper analysis and technical modification.
The lunar Askaryan technique with the Square Kilometre Array
Creators: name: James, Clancy W.
name: Alvarez-Muniz, Jaime
name: Bray, Justin D.
name: Buitink, Stijn
name: Dagkesamanskii, Rustam D.
name: Ekers, Ronald D.
name: Falcke, Heino
name: Gayley, Ken G.
name: Huege, Tim
name: Mevius, Maaijke
name: Mutel, Robert L.
name: Protheroe, Raymond J.
name: Scholten, Olaf
name: Spencer, Ralph E.
name: ter Veen, Sander
Publisher: name: arXiv
Year: 2016
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: The lunar Askaryan technique is a method to study the highest-energy cosmic rays, and their predicted counterparts, the ultra-high-energy neutrinos. By observing the Moon with a radio telescope, and searching for the characteristic nanosecond-scale Askaryan pulses emitted when a high-energy particle interacts in the outer layers of the Moon, the visible lunar surface can be used as a detection area. Several previous experiments, at Parkes, Goldstone, Kalyazin, Westerbork, the ATCA, Lovell, LOFAR, and the VLA, have developed the necessary techniques to search for these pulses, but existing instruments have lacked the necessary sensitivity to detect the known flux of cosmic rays from such a distance. This will change with the advent of the SKA. The Square Kilometre Array (SKA) will be the world's most powerful radio telescope. To be built in southern Africa, Australia and New Zealand during the next decade, it will have an unsurpassed sensitivity over the key 100 MHz to few-GHZ band. We introduce a planned experiment to use the SKA to observe the highest-energy cosmic rays and, potentially, neutrinos. The estimated event rate will be presented, along with the predicted energy and directional resolution. Prospects for directional studies with phase 1 of the SKA will be discussed, as will the major technical challenges to be overcome to make full use of this powerful instrument. Finally, we show how phase 2 of the SKA could provide a vast increase in the number of detected cosmic rays at the highest energies, and thus to provide new insight into their spectrum and origin.
description: 8 pages, 6 figures. Proceedings of the 34th International Cosmic Ray Conference, Den Haag, The Netherlands, 2015
The Magnetohydrodynamic-Particle-In-Cell Module in Athena++: Implementation and Code Tests
Creators: name: Sun, Xiaochen
name: Bai, Xue-Ning
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Physical sciences

description: We present a new magnetohydrodynamic-particle-in-cell (MHD-PIC) code integrated into the Athena++ framework. It treats energetic particles as in conventional PIC codes while the rest of thermal plasmas are treated as background fluid described by MHD, thus primarily targeting at multi-scale astrophysical problems involving the kinetic physics of the cosmic-rays (CRs). The code is optimized toward efficient vectorization in interpolation and particle deposits, with excellent parallel scaling. The code is also compatible with static/adaptive mesh refinement, with dynamic load balancing to further enhance multi-scale simulations. In addition, we have implemented a compressing/expanding box framework which allows adiabatic driving of CR pressure anisotropy, as well as the $δf$ method that can dramatically reduce Poisson noise in problems where distribution function $f$ is only expected to slightly deviate from the background. The code performance is demonstrated over a series of benchmark test problems including particle acceleration in non-relativistic parallel shocks. In particular, we reproduce the linear growth of the CR gyro-resonant (streaming and pressure anisotropy) instabilities, under both the periodic and expanding/compressing box setting. We anticipate the code to open up the avenue for a wide range of astrophysical and plasma physics applications.
description: 20 pages, 19 figures, submitted to MNRAS
Pickup Ion Effect of the Solar Wind Interaction with the Local Interstellar Medium
Creators: name: Pogorelov, Nikolai V.
name: Bedford, Matthew C.
name: Kryukov, Igor A.
name: Zank, Gary P.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Space Physics (physics.space-ph)
subject: FOS: Physical sciences

description: Pickup ions are created when interstellar neutral atoms resonantly exchange charge with the solar wind (SW) ions, especially in the supersonic part of the wind, where they carry most of the plasma pressure. Here we present numerical simulation results of the 3D heliospheric interface treating pickup ions as a separate proton fluid. To satisfy the fundamental conservation laws, we solve the system of equations describing the flow of the mixture of electrons, thermal protons, and pickup ions. To find the density and pressure of pickup ions behind the termination shock, we employ simple boundary conditions that take into account the \emph{Voyager} observations that showed that the decrease in the kinetic energy of the mixture at the termination shock predominantly contributed to the increase in the pressure of pickup ions. We show that this model adequately describes the flow of the plasma mixture and results in a noticeable decrease in the heliosheath width.
description: Accepted for publication in Journal of Physics, Conference Series
Can stellar activity make a planet seem misaligned?
Creators: name: Oshagh, M.
name: Dreizler, S.
name: Santos, N. C.
name: Figueira, P.
name: Reiners, A.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Several studies have shown that the occultation of stellar active regions by the transiting planet can generate anomalies in the high-precision transit light curves, and these anomalies may lead to an inaccurate estimate of the planetary parameters (e.g., the planet radius). Since the physics and geometry behind the transit light curve and the Rossiter- McLaughlin effect (spectroscopic transit) are the same, the Rossiter-McLaughlin observations are expected to be affected by the occultation of stellar active regions in a similar way. In this paper we perform a fundamental test on the spin-orbit angles as derived by Rossiter-McLaughlin measurements, and we examine the impact of the occultation of stellar active regions by the transiting planet on the spin-orbit angle estimations. Our results show that the inaccurate estimation on the spin-orbit angle due to stellar activity can be quite significant (up to 30 degrees), particularly for the edge-on, aligned, and small transiting planets. Therefore, our results suggest that the aligned transiting planets are the ones that can be easily misinterpreted as misaligned owing to the stellar activity. In other words, the biases introduced by ignoring stellar activity are unlikely to be the culprit for the highly misaligned systems.
description: 8 pages, 8 figures, accepted for publication in Astronomy & Astrophysics
Review Protocol: EFFECTIVENESS OF SPINAL MANIPULATION AND MOBILISATION FOR TREATING HEADACHE, AND NECK AND BACK PAIN IN PAEDIATRIC POPULATIONS: A SYSTEMATIC REVIEW
Creators: name: Pool, Jan
name: Basson, Annalie
name: Cristofoli, Taylor
name: Stiel, Kylie
name: Olson, Ken
name: Milne, Nikki
name: Macdonald, Kirstin
name: Gross, Anita
name: Smarrelli, Nathan
Publisher: name: OSF Registries
Year: 2023
Subjects: subject: Medicine and Health Sciences

description: This planned systematic review represents a focused area of research to explore the effectiveness and harms of spinal manipulation and mobilisation for treating headache, and neck and back pain in paediatric populations. If data allows, a meta-analysis will be undertaken.
Beating Rayleigh's Curse by Imaging Using Phase Information
Creators: name: Tham, Weng Kian
name: Ferretti, Hugo
name: Steinberg, Aephraim M.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Optics (physics.optics)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Any imaging device such as a microscope or telescope has a resolution limit, a minimum separation it can resolve between two objects or sources; this limit is typically defined by "Rayleigh's criterion", although in recent years there have been a number of high-profile techniques demonstrating that Rayleigh's limit can be surpassed under particular sets of conditions. Quantum information and quantum metrology have given us new ways to approach measurement ; a new proposal inspired by these ideas has now re-examined the problem of trying to estimate the separation between two poorly resolved point sources. The "Fisher information" provides the inverse of the Cramer-Rao bound, the lowest variance achievable for an unbiased estimator. For a given imaging system and a fixed number of collected photons, Tsang, Nair and Lu observed that the Fisher information carried by the intensity of the light in the image-plane (the only information available to traditional techniques, including previous super-resolution approaches) falls to zero as the separation between the sources decreases; this is known as "Rayleigh's Curse." On the other hand, when they calculated the quantum Fisher information of the full electromagnetic field (including amplitude and phase information), they found it remains constant. In other words, there is infinitely more information available about the separation of the sources in the phase of the field than in the intensity alone. Here we implement a proof-of-principle system which makes use of the phase information, and demonstrate a greatly improved ability to estimate the distance between a pair of closely-separated sources, and immunity to Rayleigh's curse.
Variations of cosmic large-scale structure covariance matrices across parameter space
Creators: name: Reischke, Robert
name: Kiessling, Alina
name: Schäfer, Björn Malte
Publisher: name: arXiv
Year: 2016
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: The likelihood function for cosmological parameters, given by e.g. weak lensing shear measurements, depends on contributions to the covariance induced by the nonlinear evolution of the cosmic web. As nonlinear clustering to date has only been described by numerical $N$-body simulations in a reliable and sufficiently precise way, the necessary computational costs for estimating those covariances at different points in parameter space are tremendous. In this work we describe the change of the matter covariance and of the weak lensing covariance matrix as a function of cosmological parameters by constructing a suitable basis, where we model the contribution to the covariance from nonlinear structure formation using Eulerian perturbation theory at third order. We show that our formalism is capable of dealing with large matrices and reproduces expected degeneracies and scaling with cosmological parameters in a reliable way. Comparing our analytical results to numerical simulations we find that the method describes the variation of the covariance matrix found in the SUNGLASS weak lensing simulation pipeline within the errors at one-loop and tree-level for the spectrum and the trispectrum, respectively, for multipoles up to $\ell\leq 1300$. We show that it is possible to optimize the sampling of parameter space where numerical simulations should be carried out by minimising interpolation errors and propose a corresponding method to distribute points in parameter space in an economical way.
description: 10 pages, 6 figures, submitted to MNRAS
Observational constraints on two cosmological models of $f(Q)$ theory
Creators: name: Koussour, M.
name: De, Avik
Publisher: name: arXiv
Year: 2023
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: In the past few years, $f(Q)$ theories have drawn a lot of research attention in replacing Einstein's theory of gravity successfully. The current study examines the novel cosmological possibilities emerging from two specific classes of $f(Q)$ models using the parametrization form of the equation of state (EoS) parameter as $ω\left( z\right) =-\frac{1}{1+3β\left( 1+z\right) ^{3}}$, which displays quintessence behavior with the evolution of the Universe. We do statistical analyses using the Markov chain Monte Carlo (MCMC) method and background datasets like Type Ia Supernovae (SNe Ia) luminosities and direct Hubble datasets (from cosmic clocks), and Baryon Acoustic Oscillations (BAO) datasets. This lets us compare these new ideas about the Universe to the $Λ$CDM model in a number of different possible ways. We have come to the conclusion that, at the current level of accuracy, the values of their specific parameters are the best fits for our $f(Q)$ models. To conclude the accelerating behavior of the Universe, we further study the evolution of energy density, pressure, and deceleration parameter for these $f(Q)$ models.
description: EPJC accepted version
Eigenvalue Dynamics for Multimatrix Models
Creators: name: Koch, Robert de Mello
name: Gossman, David
name: Nkumane, Lwazi
name: Tribelhorn, Laila
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: By performing explicit computations of correlation functions, we find evidence that there is a sector of the two matrix model defined by the $SU(2)$ sector of ${\cal N}=4$ super Yang-Mills theory, that can be reduced to eigenvalue dynamics. There is an interesting generalization of the usual Van der Monde determinant that plays a role. The observables we study are the BPS operators of the $SU(2)$ sector and include traces of products of both matrices, which are genuine multi matrix observables. These operators are associated to supergravity solutions of string theory.
description: 28+1 pages
Detecting topological exceptional points in a parity-time symmetric system with cold atoms
Creators: name: Xu, Jian
name: Du, Yan-Xiong
name: Huang, Wei
name: Zhang, Dan-Wei
Publisher: name: arXiv
Year: 2016
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We reveal a novel topological property of the exceptional points in a two-level parity-time symmetric system and then propose a scheme to detect the topological exceptional points in the system, which is embedded in a larger Hilbert space constructed by a four-level cold atomic system. We show that a tunable parameter in the presented system for simulating the non-Hermitian Hamiltonian can be tuned to swept the eigenstates through the exceptional points in parameter space. The non-trivial Berry phases of the eigenstates obtained in this loop from the exceptional points can be measured by the atomic interferometry. Since the proposed operations and detection are experimentally feasible, our scheme may pave a promising way to explore the novel properties of non-Hermitian systems.
Large Sets Avoiding Patterns
Creators: name: Fraser, Robert
name: Pramanik, Malabika
Publisher: name: arXiv
Year: 2016
Subjects: subject: Classical Analysis and ODEs (math.CA)
subject: FOS: Mathematics
subject: 28A78

description: We construct subsets of Euclidean space of large Hausdorff dimension and full Minkowski dimension that do not contain nontrivial patterns described by the zero sets of functions. The results are of two types. Given a countable collection of $v$-variate vector-valued functions $f_q : (\mathbb{R}^{n})^v \to \mathbb{R}^m$ satisfying a mild regularity condition, we obtain a subset of $\mathbb{R}^n$ of Hausdorff dimension $\frac{m}{v-1}$ that avoids the zeros of $f_q$ for every $q$. We also find a set that simultaneously avoids the zero sets of a family of uncountably many functions sharing the same linearization. In contrast with previous work, our construction allows for non-polynomial functions as well as uncountably many patterns. In addition, it highlights the dimensional dependence of the avoiding set on $v$, the number of input variables.
description: 26 Pages
Tuning the valley and chiral quantum state of Dirac electrons in van der Waals heterostructures
Creators: name: Wallbank, J. R.
name: Ghazaryan, D.
name: Misra, A.
name: Cao, Y.
name: Tu, J. S.
name: Piot, B. A.
name: Potemski, M.
name: Pezzini, S.
name: Wiedmann, S.
name: Zeitler, U.
name: Lane, T. L. M.
name: Morozov, S. V.
name: Greenaway, M. T.
name: Eaves, L.
name: Geim, A. K.
name: Fal'ko, V. I.
name: Novoselov, K. S.
name: Mishchenko, A.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Chirality is a fundamental property of electrons with the relativistic spectrum found in graphene and topological insulators. It plays a crucial role in relativistic phenomena, such as Klein tunneling, but it is difficult to visualize directly. Here we report the direct observation and manipulation of chirality and pseudospin polarization in the tunneling of electrons between two almost perfectly aligned graphene crystals. We use a strong in-plane magnetic field as a tool to resolve the contributions of the chiral electronic states that have a phase difference between the two components of their vector wavefunction. Our experiments not only shed light on chirality, but also demonstrate a technique for preparing graphene's Dirac electrons in a particular quantum chiral state in a selected valley.
description: 26 pages, 13 figures
Wythoffian Skeletal Polyhedra in Ordinary Space, I
Creators: name: Schulte, Egon
name: Williams, Abigail
Publisher: name: arXiv
Year: 2016
Subjects: subject: Metric Geometry (math.MG)
subject: Combinatorics (math.CO)
subject: FOS: Mathematics
subject: 51M20, 52B15

description: Skeletal polyhedra are discrete structures made up of finite, flat or skew, or infinite, helical or zigzag, polygons as faces, with two faces on each edge and a circular vertex-figure at each vertex. When a variant of Wythoff's construction is applied to the forty-eight regular skeletal polyhedra (Grunbaum-Dress polyhedra) in ordinary space, new highly symmetric skeletal polyhedra arise as "truncations" of the original polyhedra. These Wythoffians are vertex-transitive and often feature vertex configurations with an attractive mix of different face shapes. The present paper describes the blueprint for the construction and treats the Wythoffians for distinguished classes of regular polyhedra. The Wythoffians for the remaining classes of regular polyhedra will be discussed in Part II, by the second author. We also examine when the construction produces uniform skeletal polyhedra.
Nanograin densities outside Saturn's A-ring
Creators: name: Johnson, Robert E
name: Tseng, Wei-Lin
name: Elrod, Meredith K
name: Persoon, Ann M
Publisher: name: arXiv
Year: 2016
Subjects: subject: Space Physics (physics.space-ph)
subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: The observed disparity between the radial dependence of the ion and electron densities measured by the Cassini plasma and radio science instruments are used to show that the region between the outer edge of Saturn's main rings and its tenuous G-ring is permeated with small charged grains (nanograins). These grains emanate from the edge of the A-ring and from the tenuous F-ring and G-ring. This is a region of Saturn's magnetosphere that is relatively unexplored, but will be a focus of Cassini's F-ring orbits prior to the end of mission in September 2017. Confirmation of the grain densities predicted here will enhance our ability to describe the formation and destruction of material in this important region of Saturn's magnetosphere.
description: 8 pages, 1 figure
Point of Care Ultrasound in Critical Care Obstetrics: A Scoping Review of the Current Evidence
Creators: name: Martins, Juliana Gevaerd
name: Kawakita, Tetsuya
name: Waller, Jerri
name: Saade, George
name: Kanaan, Camille
name: Horgan, Rebecca
name: Abuhamad, Alfred
Publisher: name: OSF Registries
Year: 2023
Subjects: subject: Medical Sciences
subject: Obstetrics and Gynecology
subject: Medicine and Health Sciences
subject: Medical Specialties

description: A scoping review summarizing evidence to date regarding the use of point of care ultrasound in critical care obstetrics.
Metastability of Mn$^{3+}$ in ZnO driven by strong $d$(Mn) intrashell Coulomb repulsion: experiment and theory
Creators: name: Ciechan, A.
name: Przybylińska, H.
name: Bogusławski, P.
name: Suchocki, A.
name: Grochot, A.
name: Mycielski, A.
name: Skupiński, P.
name: Grasza, K.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Depopulation of the Mn$^{2+}$ state in ZnO:Mn upon illumination, monitored by quenching of the Mn$^{2+}$ EPR signal intensity, was observed at temperatures below 80~K. Mn$^{2+}$ photoquenching is shown to result from the Mn$^{2+}$ $\to$ Mn$^{3+}$ ionization transition, promoting one electron to the conduction band. Temperature dependence of this process indicates the existence of an energy barrier for electron recapture of the order of 1~meV. GGA$+U$ calculations show that after ionization of Mn$^{2+}$ a moderate breathing lattice relaxation in the 3+ charge state occurs, which increases energies of $d$(Mn) levels. At its equilibrium atomic configuration, Mn$^{3+}$ is metastable since the direct capture of photo-electron is not possible. The metastability is mainly driven by the strong intra-shell Coulomb repulsion between $d$(Mn) electrons. Both the estimated barrier for electron capture and the photoionization energy are in good agreement with the experimental values.
description: 11 pages, 11 figures, 1 table
Is there substructure around M87?
Creators: name: Oldham, L. J.
name: Evans, N. W.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We present a general method to identify infalling substructure in discrete datasets with position and line-of-sight velocity data. We exploit the fact that galaxies falling onto a brightest cluster galaxy (BCG) in a virialised cluster, or dwarf satellites falling onto a central galaxy like the Milky Way, follow nearly radial orbits. If the orbits are exactly radial, we show how to find the probability distribution for a satellite's energy, given a tracer density for the satellite population, by solving an Abel integral equation. This is an extension of Eddington (1916)'s classical formula for the isotropic distribution function. When applied to a system of galaxies, clustering in energy space can then be quantified using the Kullback-Leibler divergence, and groups of objects can be identified which, though separated in the sky, may be falling in on the same orbit. This method is tested using mock data and applied to the satellite galaxy population around M87, the BCG in Virgo, and a number of associations are found which may represent infalling galaxy groups.
description: 9 pages, 6 figures, 2 tables. Accepted for publication in MNRAS
Affective Motivations for Substance Misuse Modulate Consideration of Multiple Costs During Effortful Decision-Making
Creators: name: Ruiz, Sonia
Publisher: name: OSF Registries
Year: 2023
Subjects: subject: Clinical Psychology
subject: Social and Behavioral Sciences
subject: Psychology
subject: FOS: Psychology
subject: Affective motivations
subject: Approach motivation
subject: Avoidance motivation
subject: Computational modeling
subject: Cost-benefit decision-making
subject: Subjective value
subject: Substance use

description: This registration provides all raw data used to produce results for the research article for this project, as well as a codebook explaining the variables.
Performing SU($d$) operations and rudimentary algorithms in a superconducting transmon qudit for $d=3$ and $d=4$
Creators: name: Liu, Pei
name: Wang, Ruixia
name: Zhang, Jing-Ning
name: Zhang, Yingshan
name: Cai, Xiaoxia
name: Xu, Huikai
name: Li, Zhiyuan
name: Han, Jiaxiu
name: Li, Xuegang
name: Xue, Guangming
name: Liu, Weiyang
name: You, Li
name: Jin, Yirong
name: Yu, Haifeng
Publisher: name: arXiv
Year: 2023
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Quantum computation architecture based on $d$-level systems, or qudits, has attracted considerable attention recently due to their enlarged Hilbert space. Extensive theoretical and experimental studies have addressed aspects of algorithms and benchmarking techniques for qudit-based quantum computation and quantum information processing. Here, we report a physical realization of qudit with upto 4 embedded levels in a superconducting transmon, demonstrating high-fidelity initialization, manipulation, and simultaneous multi-level readout. In addition to constructing SU($d$) operations and benchmarking protocols for quantum state tomography, quantum process tomography, and randomized benchmarking etc, we experimentally carry out these operations for $d=3$ and $d=4$. Moreover, we perform prototypical quantum algorithms and observe outcomes consistent with expectations. Our work will hopefully stimulate further research interest in developing manipulation protocols and efficient applications for quantum processors with qudits.
description: Submitted to the Physical Review X; Received 19 October 2022; accepted 3 April 2023
Dimensional reduction of the Luttinger Hamiltonian and g-factors of holes in symmetric two-dimensional semiconductor heterostructures
Creators: name: Miserev, D. S.
name: Sushkov, O. P.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: The spin-orbit interaction of holes in zinc-blende semiconductors is much stronger than that of electrons. This makes the hole systems very attractive for possible spintronics applications. In three dimensions (3D) dynamics of holes is described by well known Luttinger Hamiltonian. However, most of recent spintronics applications are related to two dimensional heterostructures where dynamics in one direction is frozen due to quantum confinement. The confinement results in dimensional reduction of the Luttinger Hamiltonian, 3D ->2D. Due to interplay of the spin-orbit interaction, the external magnetic field, and the lateral gate potential imposed on the heterostructure the reduction is highly nontrivial and not known. In the present work we perform the reduction and hence derive the general effective Hamiltonian which describes spintronics effects in symmetric two-dimensional (2D) heterostructures. In particular, we do the following, (i) derive the spin-orbit interaction and the Darwin interaction related to the lateral gate potential, (ii) determine the momentum dependent out-of-plane g-factor, (iii) point out that there are two independent in-plane g-factors, (iv) determine momentum dependencies of the in-plane g-factors.
description: 9 pages, 22 figures
Uterus Transplantation: A Scoping Review From 2000 through 2023
Creators: name: Cervantes, Martha Sofía Espinosa
name: Márquez, Mario Isaac Lumbreras
name: Wolff, Megan Barragan
Publisher: name: OSF Registries
Year: 2023
Subjects: subject: Medical Sciences
subject: Obstetrics and Gynecology
subject: Medicine and Health Sciences
subject: Medical Specialties

description: Uterus transplantation (UT) proposes an innovative treatment to many causes of infertility. Given the limited use of the procedure and its important bioethical considerations, little is standardized in UT increasing maternal risk. The purpose of this review is to analyze which patient and donor conditions affect obstetric outcomes after uterus transplantation, thus delimiting the optimal patient and donor selection in light of the available data to further increase success when seeking UT.
Limits on Planetary Companions from Doppler Surveys of Nearby Stars
Creators: name: Howard, Andrew W.
name: Fulton, Benjamin J.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: Most of our knowledge of planets orbiting nearby stars comes from Doppler surveys. For spaced-based, high-contrast imaging missions, nearby stars with Doppler-discovered planets are attractive targets. The known orbits tell imaging missions where and when to observe, and the dynamically-determined masses provide important constraints for the interpretation of planetary spectra. Quantifying the set of planet masses and orbits that could have been detected will enable more efficient planet discovery and characterization. We analyzed Doppler measurements from Lick and Keck Observatories collected by the California Planet Survey. We focused on stars that are likely targets for three space-based planet imaging mission concepts studied by NASA--WFIRST-AFTA, Exo-C, and Exo-S. The Doppler targets are primarily F8 and later main sequence stars, with observations spanning 1987-2014. We identified 76 stars with Doppler measurements from the prospective mission target lists. We developed an automated planet search and a methodology to estimate the pipeline completeness using injection and recovery tests. We applied this machinery to the Doppler data and computed planet detection limits for each star as a function of planet minimum mass and semi-major axis. For typical stars in the survey, we are sensitive to approximately Saturn-mass planets inside of 1 AU, Jupiter-mass planets inside of ~3 AU, and our sensitivity declines out to ~10 AU. For the best Doppler targets, we are sensitive to Neptune-mass planets in 3 AU orbits. Using an idealized model of Doppler survey completeness, we forecast the precision of future surveys of non-ideal Doppler targets that are likely targets of imaging missions.
description: Accepted to PASP, 125 pages, 89 figures, Machine-readable data products are available at http://exoplanetarchive.ipac.caltech.edu/docs/contributed_data.html
Dirichlet boundary conditions for arbitrary-shaped boundaries in stellarator-like magnetic fields for the Flux-Coordinate Independent method
Creators: name: Hill, Peter
name: Shanahan, Brendan
name: Dudson, Ben
Publisher: name: arXiv
Year: 2016
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Physical sciences

description: We present a technique for handling Dirichlet boundary conditions with the Flux Coordinate Independent (FCI) parallel derivative operator with arbitrary-shaped material geometry in general 3D magnetic fields. The FCI method constructs a finite difference scheme for $\nabla_\Vert$ by following field lines between planes and interpolating within planes. Doing so removes the need for field-aligned coordinate systems that suffer from singularities in the metric tensor at null points in the magnetic field (or equivalently, when $q \to \infty$). One cost of this method is that as the field lines are not on the mesh, they may leave the domain at any point between neighbouring planes, complicating the application of boundary conditions. The Leg Value Fill (LVF) boundary condition scheme presented here involves an extrapolation/interpolation of the boundary value onto the field line end point. The usual finite difference scheme can then be used unmodified. We implement the LVF scheme in BOUT++ and use the Method of Manufactured Solutions to verify the implementation in a rectangular domain, and show that the error scaling of the finite difference scheme isn't modified. The use of LVF for arbitrary wall geometry is outlined. We also demonstrate the feasibility of using the FCI approach in non-axisymmetric configurations for a simple diffusion model in a "straight stellarator" magnetic field. A Gaussian blob diffuses along the field lines, tracing out flux surfaces. Dirichlet boundary conditions impose a last closed flux surface (LCFS) that confines the density. Including a poloidal limiter moves the LCFS to a smaller radius. The expected scaling of the numerical perpendicular diffusion, which is a consequence of the FCI method, in stellarator-like geometry is recovered. A novel technique for increasing the parallel resolution during post-processing is also described.
On the quantization of continuous non-ultralocal integrable systems
Creators: name: Melikyan, A.
name: Weber, G.
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Exactly Solvable and Integrable Systems (nlin.SI)
subject: FOS: Physical sciences

description: We discuss the quantization of non-ultralocal integrable models directly in the continuous case, using the example of the Alday-Arutyunov-Frolov model. We show that by treating fields as distributions and regularizing the operator product, it is possible to avoid all the singularities, and allow to obtain results consistent with perturbative calculations. We illustrate these results by considering the reduction to the massive free fermion model and extracting the quantum Hamiltonian as well as other conserved charges directly from the regularized trace identities. Moreover, we show that our regularization recovers Maillet's prescription in the classical limit.
description: 33 pages, extended version of arXiv:1505.01516
Investigating the mood effects of nature sounds and soothing images in adolescents: A proof-of-concept pilot study
Creators: name: Project Soothe
Publisher: name: Open Science Framework
Year: 2023
Subjects: subject: Cognition and Perception
subject: Clinical Psychology
subject: Psychology
subject: FOS: Psychology
subject: Social and Behavioral Sciences
subject: Quantitative Psychology
subject: Developmental Psychology
subject: adolescence
subject: nature
subject: wellbeing
subject: imagery
subject: mood
subject: sound
subject: project soothe
subject: mental health

description: This is the supplementary materials to accompany the published report of this study
Dissociation of heavy quarkonium in hot QCD medium in a quasi-particle model
Creators: name: Agotiya, Vineet K.
name: Chandra, Vinod
name: Jamal, M. Yousuf
name: Nilima, Indrani
Publisher: name: arXiv
Year: 2016
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: Following a recent work on the effective description of the equations of state for hot QCD obtained from a Hard thermal loop expression for the gluon self-energy, in terms of the quasi-gluons and quasi- quark/anti-quarks with respective effective fugacities, the dissociation process of heavy quarkonium in hot QCD medium has been investigated. This has been done by investigating the medium modification to a heavy quark potential. The medium modified potential has a quite different form (a long range Coulomb tail in addition to the usual Yukawa term) in contrast to the usual picture of Debye screening. The flavor dependence of the binding energies of the heavy quarkonia states and the dissociation temperature have been obtained by employing the debye mass for pure gluonic and full QCD case computed employing the quasi-particle picture. Thus estimated dissociation patterns of the charmonium and bottomonium states, considering Debye mass from different approaches in pure gluonic case and full QCD, have shown good agreement with the other potential model studies.
description: 16 pages, two column, 10 figures: Version accepted in Phys. Rev. D
Spätantike Bildungstraditionen im Umkreis des Klosters von Lerinum. Die Kompendienwerke des Eucherius von Lyon
Creators: name: Greschat, Katharina
Publisher: name: Humboldt-Universität zu Berlin
Year: 2007
Subjects: subject: 930 Geschichte des Altertums bis ca. 499

description: Dieser Beitrag ist mit Zustimmung des Rechteinhabers (De Gruyter) frei zugänglich.
description: This article tries to contextualize the often neglected exegetical handbooks of Eucherius of Lyons in the late antique christian debates on pagan culture and education within a monastic context. It is intended to show that Eucherius and his short manuals represent the point of view of the famous aristocratic monastery of Lerinum in southern Gaul which was orientated towards the keeping of ecclesiastical tradition. Together with other writings they imparted to younger aristocrats the necessary knowledge to become a bishop or to take on an ecclesiastical function.