Miracle-dz/UniFAR-FTUs huggingface dataset:
On Groups in Which Every Subgroup of Infinite Rank Is Subnormal of Bounded Defect

Abstract A special case of the main result is as follows: Let G be a locally (soluble-by-finite) group of infinite rank in which every subgroup of infinite rank is subnormal of defect at most d. Then G is nilpotent of class bounded in terms of d only. This extends a famous theorem of Roseblade and holds, more generally, for groups G that belong to the class 𝔛 introduced by Černikov. It is also shown that G is a Dedekind group if d = 1.
Optical and mechanical tolerances for two-lens plano-aspheric laser beam shapers

This paper presents a systematic discussion of the optical and mechanical tolerances which must be addressed in order for a laser beam shaper system to perform close to the design criteria. First, a general relationship based on the intensity law of geometrical optics is presented, which relates the input and output beam profiles, and particular attention is given to the common Gaussian input beam profile. Next, the impact of collimation errors of the input beam is addressed. Then, lens mounting errors for a two-lens laser beam shaper are addressed including lens spacing, decenter, and tilt tolerances. Overall, this paper addresses actual variations of the deterministic transformation of an input irradiance profile into an output beam profile, whether it employs refractive, reflective or diffractive optical elements.
The Brauer group of graded Azumaya algebras

We study G-graded Azumaya R-algebras for R a commutative ring and G a finite abelian group, and a Brauer group formed by such algebras. A short exact sequence is obtained which relates this Brauer group with the usual Brauer group of R and with a group of graded Galois extensions of R. In case G is cyclic a second short exact sequence describes this group of graded Galois extensions in terms of the usual group of Galois extensions of R with group G and a certain group of functions on Spec(R).
Two-point boundary value problems with eigenvalue parameter contained in the boundary conditions

Synopsis In this paper it is shown that the analysis of Titchmarsh's book [32] for regular Sturm-Liouville problems on a finite closed interval carries over readily to regular problems involving the eigenvalue parameter in the boundary condition at one end-point. The manner in which this type of problem is associated with a self-adjoint operator in Hilbert space has recently been pointed out by Walter in [36], and his operator-theoretic formulation is adopted here. The use of the eigenfunction expansion is illustrated by applying it to solve a heat-conduction problem for a solid in contact with a fluid.
The emission-line spectrum above the limb of the quiet sun - 1175-1940 A

Spectra of a quiet solar region obtained at positions within and above the solar white-light limb in the wavelength region from 1175 to 1940 A are discussed. The spectra were obtained by the slit spectrograph (SO82-B) on Skylab. The spectral resolution is 0.06 A, and the projected slit area on the sun was 2 x 60 arcsec (1450 x 43500 km). Relative line intensities are presented for lines formed in the temperature region of the solar atmosphere from about 8000 to 220,000 K. Representative line profiles of both optically thin and optically thick lines are shown as a function of height above the limb. Random mass-motion velocities are deduced from the optically thin lines, and the relative intensities and profiles of the lines are discussed in terms of current theoretical models. A wavelength list with identifications is given for the spectrum obtained at +4 arcsec above the white-light limb.
The X-Ray Structure and Spectrum of the Pulsar Wind Nebula Surrounding PSR B0540–69.3

We present the first spatially resolved spectral study of an extragalactic pulsar wind nebula (PWN), that surrounding the 50 ms pulsar B0540-69.3 in the Large Magellanic Cloud, using the ACIS instrument on board the Chandra X-ray Observatory. The spectral properties of the PWN change at a radius of ~5'', corresponding to a shell detected optically in [O III]. Within this radius, the spectra are well characterized by a simple power law, whose spectral index varies strongly with radius, so that the effective size of the nebula decreases with increasing photon energy. These X-ray measurements support the idea that the [O III] shell represents an outer skin surrounding the wind nebula, analogous to that seen in the Crab Nebula. We use the size-energy relation and radial variability of the X-ray spectral index to estimate PWN parameters, including the radial dependence of the magnetic field, and the average ratio of electromagnetic to particle flux.
Evidence for Current-carrying Emerging Flux

To determine the relationship between electric currents and magnetic flux in emerging sunspots, we use observations of the morphology, proper motion, magnetic flux, and currents associated with several well-observed growing bipoles. Our target was NOAA Active Region 7260, which included a preexisting large spot and a fast-growing area of new magnetic flux. Magnetic bipoles in this region are well documented by X-ray images from the Yohkoh spacecraft and optical images and vector magnetograms from several ground-based observatories. In this paper we show that (1) the Hα and X-ray structures associated with these bipoles do not agree with potential-field extrapolations of magnetograms; (2) proper motions imply that the flux bundles that make up these new bipoles are twisted before they emerge; (3) these new bipoles are cospatial with significant vertical electric currents; (4) the morphology, proper motion, and measured currents of these bipoles all imply the same sense of twist; (5) this sense of twist is the same as the large-scale twist of the preexisting large spot; and (6) the increase of these currents, as new flux emerges, is not consistent with their generation by photospheric motions. We conclude that the new magnetic flux that emerged in this active region carried currents generated below the photosphere. © 1996. The American Astronomical Society. All rights reserved.
Spin chains with trapped electrons

We propose to use a linear array of singly trapped electrons to implement a spin chain for quantum communication. The effective spin-spin interaction is realized by means of a magnetic field gradient, which couples the electron spin to the motional degrees of freedom. Then the Coulomb repulsion between the particles transmits this coupling throughout the array. The resulting system can be described in terms of a Heisenberg model with long-range interactions showing a dipolar decay. We estimate the fidelity of the system in reproducing an ideal spin chain by taking into account the influence of the electron spatial motion.
For nonlinear infinite dimensional equations, which to begin with: Linearization or discretization?

To tackle a nonlinear equation in a func- tional space, two numerical processes are involved: discretization and linearization. In this paper we study the di(cid:11)erences between applying them in one or in the other order. Linearize (cid:12)rst and discretize the linear problem will be in the sequel called option (A). Discretize (cid:12)rst and linearize the discrete problem will be called option (B). As a linearization scheme, we consider the Newton method. It will be shown that, under certain assumptions on the discretiza- tion method, option (A) converges to the exact solution, contrarily to option (B) which converges to a (cid:12)nite dimen- sional solution. These assumptions are not satis(cid:12)ed by the classical Galerkin, Petrov-Galerkin and collocation methods, but they are ful(cid:12)lled by the Kantorovich projection method. The problem to be solved is a nonlinear Fredholm equation of the second kind involving a compact operator. Numerical evidence is provided with a nonlinear integral equation.
Estimating visibility amplitudes with the PRIMA fringe trackers

The quality of the tracking performed by the fringe sensor units (FSUs) of PRIMA, the ESO’s dual feed facility for the VLTI, is affected by the angular separation between the two objects being observed simultaneously, the detector integration time (DIT) and the atmospheric observational conditions. We describe the algorithm we developed to compute visibilities from the FSU data and discuss their validity for the study on the angular anisoplanatism measured through the dependence of the visibility amplitudes on the angular separation.
Extragalactic Globular Clusters. III. Metallicity Comparisons and Anomalies

Using a method based on the strengths of six absorption line indices measured in integrated spectra, we have derived metallicities for 22 globular clusters associated with the Sc galaxy, M33, 10 globular clusters associated with the giant elliptical galaxy, M87, eight globular clusters associated with the Sb(r)I-II galaxy, M81, and three globular clusters associated with the Fornax dwarf elliptical galaxy. In addition, we have derived mean metallicities for 38 bright galaxies, mostly ellipticals, 29 dwarf elliptical galaxies in the Virgo cluster, 10 dwarf elliptical galaxies in the Fornax cluster and four local group dwarf galaxies
Effects of Adherence to Once-Daily Treatment on Lung Function, Bronchial Hyperreactivity and Health Outcomes in Adolescents with Mild-to-Moderate Asthmoka: A Twelve-Month Survey

Adolescents with asthma are usually insufficiently adherent to regular inhalation treatments, thus limiting their effectiveness. The aim of this study is to investigate the role of adherence to single-inhaler long-acting LABA/ICS dry-powder combination o.d. in affecting lung function, bronchial hyperreactivity, and health outcomes over a twelve-month survey of a group of non-smoking adolescents with mild to moderate asthma. Methods: Age, gender, BMI and atopy, forced expiratory volume in 1 s (FEV1), maximum mid-expiratory flow (MMEF), and maximum expiratory flow at 25% of lung filling (MEF25) were assessed via a Boolean selection process from the institutional database at recruitment, as well as after 6 and 12 months, together with the incidence of exacerbation, school days that were taken off, GP and specialist visits, and systemic steroid and/or antibiotic courses. Adherence was checked monthly via a direct telephone call. Statistics were calculated with an ANOVA trend analysis, assuming p < 0.05. Results: Two well-matched sample groups of 54 subjects each were obtained. The mean annual adherence to treatment ranged from 48.2% doses ± 10.9 sd to 79.3% doses ± 8.8 sd (p < 0.001), regardless of age and gender. Only adolescents that adhered to the o.d. ICS/LABA inhalation regimen progressively achieved complete control of all lung function parameters (FEV1: 0.001; MMEF: p < 0.002; MEF25 < 0.001; <0.001), minimized their bronchial hyperreactivity (p < 0.001), and optimized all health outcomes (p < 0.001—p < 0.002) over the survey duration. Discussion: A good adherence to treatment is essential for asthma management, particularly in young patients. Factors that are totally independent of the complexity of the therapeutic regimen adopted (namely, only a once-daily inhalation in the present survey) probably represent the major reasons limiting the adolescents’ adherence. Cultural, educational, behavioral, and psychological factors are frequently involved, are difficult to control, and can present barriers to adolescents’ asthma management. Further studies aiming to deeply understand and possibly remove the reasons for such adolescents’ attitudes are needed, in cooperation with actions oriented in this direction by families, educators, and health professionals.
Proteomic Analysis of Barley (Hordeum vulgare L.) Leaves in Response to Date Palm Waste Compost Application

Composts are an emerging biofertilizers used in agronomy that can improve crop performance, but much less is known regarding their modes of action. The current study aimed to investigate the differentially abundant proteins (DAPs) in barley leaves associated with growth promotion induced by application of date palm waste compost. Morphophysiological measurements revealed that compost induced a significant increase in plant height, chlorophyll content, gas exchange parameters and plant biomass. LC-MS/MS analyses indicate that compost induced global changes in the proteome of barley leaves. A total of 62 DAPs (26 upregulated and 36 downregulated) among a total of 2233 proteins were identified in response to compost application. The expression of DAPs was further validated based on qRT-PCR. Compost application showed altered abundance of several proteins related to abiotic stress, plant defense, redox homeostasis, transport, tricarboxylic acid cycle, carbohydrate, amino acid, energy and protein metabolism. Furthermore, proteins related to metabolic processes of phytohormone, DNA methylation and secondary metabolites were induced. These results indicate that barley responds to compost application by complex metabolism pathways and may result in a positive alteration in a physiological and metabolic barley plant state which consequently could lead to improved growth and stress adaptation observed in compost-treated plants.
Discerning multiplicative and additive reasoning in co-variation problems

In this study of arithmetical reasoning, which extends earlier work, we explore what properties students, when working in pairs, discern in additive and multiplicative co-variation problems that help them to distinguish between problem types. Results showed that pairs who solved each problem appropriately discerned mathematically significant properties such as speed, starting time and distance. Pairs who over-used additive reasoning focused on the distance difference without considering speed. While speed is considered to be a difficult quantity, here it seems to help students distinguish between multiplicative and additive situations.
Visual observations of the flow past a sphere at Reynolds numbers between 104 and 106

The wake configuration of a sphere has been determined by means of the surface oil-flow method, the smoke method and the tuft-grid method in a wind tunnel at Reynolds numbers ranging from 104 to 106. It was found that the wake performs a progressive wave motion at Reynolds numbers between 104 and 3·8 × 105, and that it forms a pair of stream wise line vortices at Reynolds numbers between 3·8 × 105 and 106.
Transparent conductive films based on the laser sintering of metal and metal oxide nanoparticles

The laser sintering employing a CW DPSS laser was applied to the fabrication of transparent conductive films using silver and indium tin oxide (ITO) nanoparticle inks. The laser sintering of an Ag nanoparticle thin film gave a transparent conductive film with a thickness of ca. 10 nm, whereas such a thin film fabricated by conventional heat treatment using an electronic furnace was insulator because of the formation of isolated silver grains during the slow heating process The influences of the laser sintering conditions such as laser scan speed on the conductivity and the transparency were studied. The laser sintering using ITO nanoparticle ink gave a high transparent conductive film by one step scanning of laser beam in air.
A finite element method for the compressible Stokes equations

A linearized steady-state, compressible, viscous Navier–Stokes system is considered. A finite element method is formulated. The unique solvability and stability of the finite element solution follow from a theorem for an abstract formulation. It is proved that when the subspaces for velocity and pressure satisfy the inf-sup condition associated with the (incompressible) Stokes system, the finite element method is uniquely solvable. An error estimate is obtained for the numerical approximation.
Fixed-point iterations for asymptotically nonexpansive mappings in Banach spaces

In this paper, we suggest and analyze a three-step iterative scheme for asymptotically nonexpansive mappings in Banach spaces. The new iterative scheme includes Ishikawa-type and Mann-type interations as special cases. The results obtained in this paper represent an extension as well as refinement of previous known results.
On the conservation of volume during particle coagulation

If ( delta n/ delta t)c is the coagulation rate of change of the distribution function n(v) for a system of particles, it is shown that integral 0infinity v( delta n/ delta t)c dv is not necessarily zero. Rather, depending on the coagulation kernel and the behaviour of n(v) as v to infinity , it may be zero, non-zero and finite, or infinite. This has implications for the asymptotic behaviour of the solution of the steady state, time-independent coagulation equation. The results are applied to Brownian and gravitational coagulation.
Accretion, Kinematics, and Rotation in the Orion Nebula Cluster: Initial Results from Hectochelle

We present results from high-resolution spectra of 237 stars in the Orion Nebula cluster (ONC) obtained during two engineering runs with the Hectochelle multifiber echelle spectrograph on the 6.5 m MMT. The ONC is the nearest populous young (age ∼ 1 Myr) cluster and is therefore an important object for studies of the evolution of protoplanetary disks. Using the high spectral resolution of Hectochelle, we are able to distinguish stellar accretion and wind emission-line profiles from nebular emission lines and identify accreting members of the cluster from Hα profiles with greater accuracy than previously possible. We find 15 new members on the basis of Li λ6707 absorption and Hα emission. Line profiles of Hα of some objects that are not too contaminated by nebular emission show features characteristic of mass inflow and ejection. We also present rotational velocities as part of an initial investigation into angular momentum evolution of very young stars, confirming a difference between classical T Tauri stars and weak-line T Tauri stars that had been found from period analysis. Finally, we present an initial study of the radial velocity dispersion of the brighter stars in the central cluster. The very small dispersion derived, ≤1.8 km s-1, is in good agreement with estimates from proper motions.
Evaluation of the CMCC eddy‐permitting global ocean physical reanalysis system (C‐GLORS, 1982–2012) and its assimilation components

Ocean reanalyses are data assimilative simulations, aimed at estimating the four‐dimensional state of the ocean over long periods, in a way as consistent over time as possible. They are designed for a wide range of climate applications, such as climate monitoring and low‐frequency variability studies, along with several downstream applications (e.g. biogeochemical and fishery modelling, initial conditions for long‐range coupled predictions, regional model nesting). An upgraded version of the Euro‐Mediterranean Center for Climate Change (CMCC) eddy‐permitting global ocean reanalysis, named CMCC Global Ocean Reanalysis System (C‐GLORS) version 4, was recently released. The reanalysis covers the meteorological satellite era (1982–2012). This article details the configuration of the reanalysis system and provides an extensive validation, focusing on the evaluation of main indexes related to climate monitoring. Cumulative denial experiments are also conducted, in order to understand the relative impact of assimilation components included in C‐GLORS (i.e. altimetric data, variational assimilation, bias correction and surface nudging). Results indicate that C‐GLORS proves reliable in simulating long‐term means, heat and freshwater trends, sea‐level variability, mean surface circulation and transports, eddy variability and meridional overturning circulation and its associated heat transport, except for a few specific issues (overestimation of volume transports in the Southern Ocean and slight underestimation of the Atlantic ocean meridional overturning circulation and associated heat transport, the latter mostly linked to underestimation of western boundary northward transports). The results also demonstrate the complementarity of the assimilation components, all improving verification skill scores, for example the importance of the variational assimilation for the simulation of the reanalysis small‐scale variability, the importance of the bias‐correction scheme for correcting subsurface salinity errors or the role of surface nudging in driving the North Atlantic ocean circulation. The analyses presented here offer ideas for improving C‐GLORS further and for the requirements of next‐generation ocean reanalysis systems.
Rate of convergence of an empirical regression method for solving generalized backward stochastic differential equations

This study focuses on the numerical resolution of backward stochastic differential equations with data dependent on a jump-diffusion process. We propose and analyse a numerical scheme based on iterative regression functions which are approximated by projections on vector spaces of functions, with coefficients evaluated using Monte Carlo simulations. Regarding the error, we derive explicit bounds with respect to the time step, the number of paths simulated and the number of functions: this allows us to optimally adjust the parameters to achieve a given accuracy. We also present numerical tests related to option pricing with differential interest rates and locally risk-minimizing strategies (Follmer- Schweizer decomposition).
Numerical treatment of the Black-Scholes variational inequality in computational finance

Among the central concerns in mathematical finance is the evaluation of American options. An American option gives the holder the right but not the obligation to buy or sell a certain financial asset within a certain time-frame, for a certain strike price. The valuation of American options is formulated as an optimal stopping problem. If the stock price is modelled by a geometric Brownian motion, the value of an American option is given by a deterministic parabolic free boundary value problem (FBVP) or equivalently a non-symmetric variational inequality on weighted Sobolev spaces on the entire real line R. To apply standard numerical methods, the unbounded domain is truncated to a bounded one. Applying the Fourier transform to the FBVP yields an integral representation of the solution including the free boundary explicitely. This integral representation allows to prove explicit truncation errors. Since the variational inequality is formulated within the framework of weighted Sobolev spaces, we establish a weighted Poincaré inequality with explicit determined constants. The truncation error estimate and the weighted Poncaré inequality enable a reliable a posteriori error estimate between the exact solution of the variational inequality and the semi-discrete solution of the penalised problem on R. A sufficient regular solution provides the convergence of the solution of the penalised problem to the solution of the variational inequality. An a priori error estimate for the error between the exact solution of the variational inequality and the semi-discrete solution of the penalised problem concludes the numerical analysis. The established a posteriori error estimates motivates an algorithm for adaptive mesh refinement. Numerical experiments show the improved convergence of the adaptive algorithm compared to uniform mesh refinement. The choice of different truncation points reveal the influence of the truncation error estimate on the total error estimator. This thesis provides a semi-discrete reliable a posteriori error estimates for a variational inequality on an unbounded domain including explicit truncation errors. This allows to determine a truncation point such that the total error (discretisation and truncation error) is below a given error tolerance.