Miracle-dz/UniFAR-FTUs huggingface dataset:
Interbasis expansions for the isotropic 3D harmonic oscillator and bivariate Krawtchouk polynomials

An explicit expression for the general bivariate Krawtchouk polynomials is obtained in terms of the standard Krawtchouk and dual Hahn polynomials. The bivariate Krawtchouk polynomials occur as matrix elements of the unitary reducible representations of SO(3) on the energy eigenspaces of the three-dimensional isotropic harmonic oscillator and the explicit formula is obtained from the decomposition of these representations into their irreducible components. The decomposition entails expanding the Cartesian basis states in the spherical bases that span irreducible SO(3) representations. The overlap coefficients are obtained from the Clebsch–Gordan problem for the su(1,1)? > Lie algebra.
Cell dimensions of hydrocarbon crystals: Surface effects

The unit‐cell dimensions of a given polyethylene have previously been shown to vary nearly linearly with the reciprocal of lamella thickness. Data obtained at 153.2 and 296.2°K are presented to show that the slope of this dependence is different for crystals of orthorhombic n ‐paraffins, melt‐crystallized polyethylene, and solution‐crystallized polyethylene. Within the limits of error, all extrapolate to the same basal area at infinite lamella thickness, and this agrees with the measured value for a sample crystallized from the melt under high pressure to yield a long period of about 3500 A. Since the effect is a surface one, it is proposed that these differences result from the differences between methyl interactions, fold interactions, different fold planes, domains, etc. It is shown that the variation of cell dimension with lamella thickness leads to a quadratic term in the variation of macroscopic density. This term permits the separation of the thickness and density of a lower‐density surface layer in a two‐phase model.
Photoluminescent characterization of GaAs solar cells

Photoluminescence excitation measurements are shown to accurately determine the spectral response of Ga1−xAlxAs‐GaAs heterojunction solar cells. The technique is applicable to as‐grown structures prior to processing into final devices and can also be used to study postgrowth techniques designed to enhance the spectral response of such devices. The measurements indicate that some surface recombination passivation is obtained with anodization.
Quantum quenches in the transverse field Ising chain: II. Stationary state properties

We consider the stationary state properties of the reduced density matrix as well as spin–spin correlation functions after a sudden quantum quench of the magnetic field in the transverse field Ising chain. We demonstrate that stationary state properties are described by a generalized Gibbs ensemble. We discuss the approach to the stationary state at late times.
Membership of Low-Mass Stars in the Open Cluster (Alpha) Persei

The results of a combined astrometric, photometric, and spectroscopic search for low-mass members in the intermediate-age open cluster α Persei are presented. Over 130 low-mass new members have been identified to M V ⇒ 12.5, almost doubling the previous number of known members. The new membership information suggests a slight upward revision of α Per's age to ∼8 × 10 7 yr. α Per is noticebly spatially elongated in a direction parallel to the galactic plane, most likely due to tidal deformation. Analysis of the distribution of relative Hα emission strengths among α Per members confirms the view that the mean Hα strength decreases in increasingly older systems. Allowing for survey incompleteness, one cannot reject the idea that the luminosity function is consistent with the field luminosity function to M v ⇒ 9 or 10
Some topics on Ricci solitons and self-similar solutions to mean curvature flow

In this survey article, we discuss some topics on self-similar solutions to the Ricci flow and the mean curvature flow. Self-similar solutions to the Ricci flow are known as Ricci solitons. In the first part of this paper we discuss a lower diameter bound for compact manifolds with shrinking Ricci solitons. Such a bound can be obtained from an eigenvalue estimate for a twisted Laplacian, called the Witten-Laplacian. In the second part we discuss self-similar solutions to the mean curvature flow on cone manifolds. Many results have been obtained for solutions in $\bfR^n$ or $\bfC^n$. We see that many of them extend to cone manifolds, and in particular results on $\bfC^n$ for special Lagrangians and self-shrinkers can be extended to toric Calabi-Yau cones. We also see that a similar lower diameter bound can be obtained for self-shrinkers to the mean curvature flow as in the case of shrinking Ricci solitons.
The relationship between corporate social responsibility and firm performance: evidence from Jordan

Abstract This study aims to investigate the relationship between corporate social responsibility (CSR) and Jordanian firm performance. CSR is measured using three dimensions: philanthropy, community, and environment. Meanwhile, firm performance is measured by two accounting-based measurements; Return on Assets (ROA) and Return on Equity (ROE). We employ the legitimacy theory as a theoretical perspective for the current study. The data included 200 observations of 100 service and industrial Jordanian companies listed on the Amman Stock Exchange. SPSS is used for data analysis. The results indicate a significant positive association between community and environment with both ROA and ROE. However, Philanthropy does not significantly affect ROA and ROE. Additionally, Jordanian companies seem to apply “form” when it comes to philanthropy. Organizational legitimacy is their principal management objective, not improving philanthropy disclosure practices. However, regarding community and environmental disclosures, firms seek organisational legitimacy by adopting substantive changes to the information content of such parameters. This study’s contributions are twofold. First, we expand the literature by exploring the effect of CSR disclosure on firm performance in an emerging economies context. Secondly, to our knowledge this is the first study that examines whether managers use CSR disclosures as symbolic or substantive actions to gain organisational legitimacy. As a practical implication of this study, investors should consider the companies’ community and environmental CSR activities when making investment decisions. Future research may include the mediating or moderating effect of other variables on the relationship between CSR and firm performance.
Solvability of a steady boundary-value problem for the equations of one-temperature viscous compressible heat-conducting bifluids

We consider a boundary-value problem describing the steady motion of a two-component mixture of viscous compressible heat-conducting fluids in a bounded domain. We make no simplifying assumptions except for postulating the coincidence of phase temperatures (which is physically justified in certain situations), that is, we retain all summands in equations that are a natural generalization of the Navier-Stokes-Fourier model of the motion of a one-component medium. We prove the existence of weak generalized solutions of the problem.
Some results on the length of proofs

ABSTRACT. Given a theory T, let \-^A mean "A has a proof in T of at most k lines". We consider a formulation PA* of Peano arithmetic withfull induction but addition and multiplication being ternary relations. We showthat \-k A is decidable for PA* and hence PA* is closed under a weak enrule. Ananalogue of Godel's theorem on the length of proofs is an easy corollary. 1. Introduction. In this paper we shall consider questions regarding thelengthOjof proofs. Now the length of (the shortest) proof of a given formulain a formal system depends strongly on the way in which the system is pre-sented. E.g. adjoining one of the theorems as an axiom reduces the lengthof some proofs. Thus in order to get significant results, we have either toconfine ourselves to particular formalisations of particular theories or elseto tormulate a criterion which distinguishes "nice" and "not so nice"formalisations of the same theory. We shall take here the second approach.In particular we shall consider theories formalised in some language of thelower predicate calculus by means of a finite number of axioms, axiomschemata and schematic rules of inference. Formalisations of this kind willinclude Hilbert type and Gentzen type formalisations of classical and in-tuitionistic arithmetic.2. Schematic systems. Since axiom schemata and rules of inference aregenerally explained in the literature with the help of formula variables, inorder to define the notion of a schematic system we do the obvious, namely,we expand the notation of the predicate calculus to include metamathematicalsymbols and emphasize substitution as the central idea. Precise details
Studying Sclerostin in Hemodialysis and after Kidney Transplantation in Egyptian Populations and Its Relation to Vascular Calcification: A Single Center Study

Background: Vascular calcification has been shown as a critical indicator of cardiovascular diseases and all-cause mortality in patients with chronic kidney disease. Patients with chronic kidney disease and vascular calcification were suggested to be considered at the highest cardiovascular disease risk by the kidney disease. The current study aimed to assess level of sclerostin in patients on haemodialysis and its association with vascular calcification. Patients and methods: The current study included 29 patients received a renal transplant at least 12 months ago (transplant group), 34 patients who diagnosed wth (end stage kidney disease) ESKD and receiving regular haemodialysis (ESKD group) and 30 normal individuals (control group). All cases were subjected to laboratory data including sclerostin level assessment. In addition, echocardiography and carotid intima media thickness was assessed by Duplex in patient’s group. Results: The study found that majority of subjects was males. Also, frequency of diabetes mellitus was significantly higher among dialysis group. Dialysis group had significtly higher level of sclerostin in comparison to other groups. Vascular calcification was present in 31% of transplant group and 38.2% of dialysis group. Dialysis and transplant groups had significantly higher intima media thickness but with significantly lower bone mineral density in comparison to the control group. Sclerostin had negative significant correlation with glomerular filtration rate and serum calcium and positive significant correlation with serum phosphate, parathermone hormone and intima media thickness. C onclusion: Patients with chronic kidney disease are vulnerable to develop vascular calcification. This complication is usually increasing the cardiovascular morbidity in those patients. Multi center future studies are warranted to confirm the role of sclerostin.
Minimal Asymptotic Translation Lengths of Torelli Groups and Pure Braid Groups on the Curve Graph

In this paper, we show that the minimal asymptotic translation length of the Torelli group ${\mathcal{I}}_g$ of the surface $S_g$ of genus $g$ on the curve graph asymptotically behaves like $1/g$, contrary to the mapping class group ${\textrm{Mod}}(S_g)$, which behaves like $1/g^2$. We also show that the minimal asymptotic translation length of the pure braid group ${\textrm{PB}}_n$ on the curve graph asymptotically behaves like $1/n$, contrary to the braid group ${\textrm{B}}_n$, which behaves like $1/n^2$.
Exponential Mixing and Smooth Classification of Commuting Expanding Maps

We show that genuinely higher rank expanding actions of abelian semi-groups on compact manifolds are $C^{\infty}$-conjugate to affine actions on infra-nilmanifolds. This is based on the classification of expanding diffeomorphisms up to \holder conjugacy by Gromov and Shub, and is similar to recent work on smooth classification of higher rank Anosov actions on tori and nilmanifolds. To prove regularity of the conjugacy in the higher rank setting, we establish exponential mixing of solenoid actions induced from semi-group actions by nilmanifold endomorphisms, a result of independent interest. We then proceed similar to the case of higher rank Anosov actions.
An Introduction to Chaotic Dynamical Systems

Part One: One-Dimensional Dynamics Examples of Dynamical Systems Preliminaries from Calculus Elementary Definitions Hyperbolicity An example: the quadratic family An Example: the Quadratic Family Symbolic Dynamics Topological Conjugacy Chaos Structural Stability Sarlovskiis Theorem The Schwarzian Derivative Bifurcation Theory Another View of Period Three Maps of the Circle Morse-Smale Diffeomorphisms Homoclinic Points and Bifurcations The Period-Doubling Route to Chaos The Kneeding Theory Geneaology of Periodic Units Part Two: Higher Dimensional Dynamics Preliminaries from Linear Algebra and Advanced Calculus The Dynamics of Linear Maps: Two and Three Dimensions The Horseshoe Map Hyperbolic Toral Automorphisms Hyperbolicm Toral Automorphisms Attractors The Stable and Unstable Manifold Theorem Global Results and Hyperbolic Sets The Hopf Bifurcation The Hnon Map Part Three: Complex Analytic Dynamics Preliminaries from Complex Analysis Quadratic Maps Revisited Normal Families and Exceptional Points Periodic Points The Julia Set The Geometry of Julia Sets Neutral Periodic Points The Mandelbrot Set An Example: the Exponential Function
Nematic equilibria on a two-dimensional annulus: defects and energies

We study planar nematic equilibria on a two-dimensional annulus with strong and weak tangent anchoring, within the Oseen-Frank and Landau-de Gennes theories for nematic liquid crystals. We analyse the defect-free state in the Oseen-Frank framework and obtain analytic stability criteria in terms of the elastic anisotropy, annular aspect ratio and anchoring strength. We consider radial and azimuthal perturbations of the defect-free state separately, which yields a complete stability diagram for the defect-free state. We construct nematic equilibria with an arbitrary number of defects on a two-dimensional annulus with strong tangent anchoring and compute their energies; these equilibria are generalizations of the diagonal and rotated states observed in a square. This gives novel insights into the correlation between preferred numbers of defects, their locations and the geometry. In the Landau-de Gennes framework, we adapt Mironescu's powerful stability result in the Ginzburg-Landau framework (P. Mironescu, On the stability of radial solutions of the Ginzburg-Landau equation, 1995) to compute quantitative criteria for the local stability of the defect-free state in terms of the temperature and geometry.
Tractors and twistors from conformal Cartan geometry: a gauge theoretic approach II. Twistors

Tractor and Twistor bundles provide natural conformally covariant calculi on 4D-Riemannian manifolds. They have different origins but are closely related, and usually constructed bottom–up through prolongation of defining differential equations. We propose alternative top–down gauge theoretic constructions, starting from the conformal Cartan bundle P and its vectorial E and spinorial E associated bundles. Our key ingredient is the dressing field method of gauge symmetry reduction, which allows tractors and twistors and their associated connections to exhibit as gauge fields of a non-standard kind as far as Weyl rescaling transformation is concerned. By non-standard we mean that they implement the gauge principle of physics, but are of a different geometric nature than the well-known differential geometric objects usually underlying gauge theories. We provide the corresponding BRST treatment. In a companion paper we dealt with tractors, in the present one we address the case of twistors.
Anisotropic space-time adaptation for reaction-diffusion problems

A residual error estimator is proposed for the energy norm of the error for a scalar reaction-diffusion problem and for the monodomain model used in cardiac electrophysiology. The problem is discretized using $P_1$ finite elements in space, and the backward difference formula of second order (BDF2) in time. The estimator for space makes use of anisotropic interpolation estimates, assuming only minimal regularity. Reliability of the estimator is proven under certain mild assumptions on the convergence of the approximate solution. The monodomain model couples a nonlinear parabolic partial differential equation (PDE) with an ordinary differential equation (ODE) and this setting presents challenges theoretically as well as numerically. A space-time adaptation algorithm is proposed to control the global error, using a non-Euclidean metric for mesh adaptation and a simple method to adjust the time step. Numerical examples are used to verify the reliability and efficiency of the estimator, and to test the adaptive algorithm. The potential gains in efficiency of the proposed algorithm compared to methods using uniform meshes is discussed.
Asymptotic Properties of the Electromagnetic Field

From the integral form of the general solution for the retarded electromagnetic field of a localized charge‐current distribution, the asymptotic field is shown to have the behavior Fμν = Nμν/R + IIIμν/R2 + 2Jμν/R3, where the coefficients satisfy Nμνkν = 0, IIIμνkν = Akμ, and kμkν = 0. The remainder 2Jμν is shown to be bounded by using the second‐mean‐value theorem. Thus the algebraically special character of the asymptotic electromagnetic field is exhibited.
Reduction of filtered K-theory and a characterization of Cuntz-Krieger algebras

We show that filtered K-theory is equivalent to a substantially smaller invariant for all real-rank-zero C*-algebras with certain primitive ideal spaces -- including the infinitely many so-called accordion spaces for which filtered K-theory is known to be a complete invariant. As a consequence, we give a characterization of purely infinite Cuntz-Krieger algebras whose primitive ideal space is an accordion space.
The Gieseker-Petri divisor in M_g for genus g<=13

The Gieseker-Petri locus GP_g is defined as the locus inside M_g consisting of curves which violate the Gieseker-Petri Theorem. It is known that GP_g has always some divisorial components and it has been conjectured that it is of pure codimension 1 inside M_g. We prove that this holds true for genus up to 13.
Measurement of rotational power losses in silicon-Iron sheets using wattmeter method

Development of a rotational power loss measuring system based on the wattmeter method for a single Epstein strip and a brief discussion of magnetization processes of Si-Fe sheets under the rotational magnetizing condition are described. The pick-up coil system has a configuration with a flux search coil sandwiched by two magnetic field search coils, with which the components of the field parallel and transverse to the longitudinal direction of a specimen are separately detected. The flux search coil has two windings wound along diagonal lines of a square insulator into which the specimen is inserted. Addition and subtraction of two output voltages from these windings give the signals proportional to the flux change rate in the directions parallel and transverse to the longitudinal direction of the specimen. Therefore, two values of losses corresponding to two magnetizing directions are obtained using wattmeters. Summation of these loss values gives the rotational power loss. Since magnetizing processes in both directions are closely related each other through the domain wall movement and the rotation of magnetization in the specimen, losses are quite different from those obtained from an alternating magnetization in the higher magnetization range in which even a minus loss can be observed.
Conformal nets and KK-theory

Given a completely rational conformal net A on the circle, its fusion ring acts faithfully on the K_0-group of a certain universal C*-algebra associated to A, as shown in a previous paper. We prove here that this action can actually be identified with a Kasparov product, thus paving the way for a fruitful interplay between conformal field theory and KK-theory.
Assessment of marine sediments quality of El-Dabaa area, northwestern Mediterranean coast of Egypt

The assessment of the sediment quality and degree of contamination of El-Dabaa region along the Mediterranean coast, which comprises an area selected for developing a nuclear power plant (NPP) in Egypt, is important to provide background contaminant levels of coastal sediments. Determination of 21 heavy metals concentrations (Th, U, Na, Mg, Al, K, Ca, V, Ag, Sb, Mo, Co, Ba, Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn), and geochemical analysis of bottom sediments collected from five selected stations along El-Dabaa area were studied. Contamination factor indices have been applied. Results of the correlation between the five stations reveal insignificant variations reflected homogenous environment,
Responding to Microaggressions: Social Cost of Bystander Intervention Strategies

This two-part study examined the effects of intervener’s race (White vs. Asian) and intervention format (high-threat—emphasizing the act of racism, low-threat—emphasizing the norm of justice, support-based—emphasizing a nonjudgmental attitude) on perceptions of microaggression interventions for White observers and Asian American targets. In separate 2 x 3 experimental designs, Asian Americans participants (N = 187) and White American participants (N = 185) were recruited through Qualtrics panels and randomly assigned to one of six conditions (three formats of intervention and two intervener groups). Participants read a vignette, imagined themselves as targets of the microaggression (Asian sample) or witnesses of the interaction (White sample), and completed a set of questionnaires assessing positive and negative perceptions of the intervener and aggressor. Asian American targets and White witnesses had more negative perceptions of interveners in the high threat condition. Covariates were relevant in interpreting reactions to intervention.
Round turbulent buoyant jets discharged vertically upwards forming a regular polygon

The simplified partial differential equations of momentum and tracer for the mean motion are integrated on the reduced cross-sectional area within the field of one buoyant jet from a group issued vertically upwards from a rosette-type riser. The solutions yield the dimensionless centerline axial velocities and concentrations. Mathematically, the one-jet field is separated from the entire group by employing the Entrainment Restriction Approach (ERA) applicable in interacting buoyant jets with symmetry planes. ERA was herein improved by incorporating the Second Order Approach (SOA). Interaction effects are highlighted by normalizing the mean-flow properties. The role of buoyancy on merging is introduced by a dynamic parameter, which combines proximity effects with buoyancy, thus termed dynamic proximity number. In addition, the distributions for mean dilution, kinetic energy flux and local Richardson number are also predicted, discussed, and compared with data reported in the literature. Findings may be useful for design purposes and environmental impact assessment.
Some knots with surgeries yielding lens spaces

This is a facsimile of the circa 1990 unpublished manuscript with the same title. All the original text, figures and tables are included; although text has been reset in \TeX, the original hand-drawn figures have been redrawn digitally, and the parameter $k$ in the original table of lens spaces has been replaced with the originally intended $\lambda$. And, of course, this abstract has been added.
Logic Blog 2018

Logic Blog 2017 (Link: http://arxiv.org/abs/1804.05331) Logic Blog 2016 (Link: http://arxiv.org/abs/1703.01573) Logic Blog 2015 (Link: http://arxiv.org/abs/1602.04432) Logic Blog 2014 (Link: http://arxiv.org/abs/1504.08163) Logic Blog 2013 (Link: http://arxiv.org/abs/1403.5719) Logic Blog 2012 (Link: http://arxiv.org/abs/1302.3686) Logic Blog 2011 (Link: http://arxiv.org/abs/1403.5721) Logic Blog 2010 (Link: http://dx.doi.org/2292/9821)