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Rational Empiricism : The idealist view of (elementary) physics

This book attempts to reconstruct elementary physics in full compliance with reason, thus continuing the work of philosophers (experimental and mathematical) throughout the centuries. The unabridged Newton's mechanics is recovered, Gauss intuitions about relational electromagnetism are developed and completed and Schrödingers undulatory quantum theory is reproposed, unifying all three theories in

Self-adjoint difference operators and symmetric Al-Salam-Chihara polynomials

The symmetric Al-Salam-Chihara polynomials for q > 1 are associated with an indeterminate moment problem. There is a self-adjoint second-order difference operator on 2(Z) to which these polynomials are eigenfunctions. We determine the spectral decomposition of this self-adjoint operator. This leads to a class of discrete orthogonality measures, which have been obtained previously by Christiansen a

Spectral properties of a q-Sturm-Liouville operator

We study the spectral properties of a class of Sturm-Liouville type operators on the real line where the derivatives are replaced by a q-difference operator which has been introduced in the context of orthogonal polynomials. Using the relation of this operator to a direct integral of doubly-infinite Jacobi matrices, we construct examples for isolated pure point, dense pure point, purely absolutely

Self-adjoint difference operators and classical solutions to the Stieltjes-Wigert moment problem

The Stieltjes-Wigert polynomials, which correspond to an indeterminate moment problem on the positive half-line, are eigenfunctions of a second order q-difference operator. We consider the orthogonality measures for which the difference operator is symmetric in the corresponding weighted L2-spaces. Under some additional assumptions these measures are exactly the solutions to the q-Pearson equation

Finite gap Jacobi matrices : An announcement

We consider Jacobi matrices whose essential spectrum is a finite union of closed intervals. We focus on Szego{double acute}'s theorem, Jost solutions, and Szego{double acute} asymptotics for this situation. This announcement describes talks the authors gave at OPSFA 2007.

Weak equivalence of local independence graphs

Classical graphical modeling of random vectors uses graphs to encode conditional independence. In graphical modeling of multivariate stochastic processes, graphs may encode so-called local independence analogously. If some coordinate processes of the multivariate stochastic process are unobserved, the local independence graph of the observed coordinate processes is a directed mixed graph (DMG). Tw

Finite Gap Jacobi Matrices, II. The Szego{double acute} Class

Let e ⊂ ℝ be a finite union of disjoint closed intervals. We study measures whose essential support is e and whose discrete eigenvalues obey a 1/2-power condition. We show that a Szego{double acute} condition is equivalent to (this includes prior results of Widom and Peherstorfer-Yuditskii). Using Remling's extension of the Denisov-Rakhmanov theorem and an analysis of Jost functions, we provide a

Encyclopedia of Special Functions : The Askey-Bateman Project: Volume 1: Univariate Orthogonal Polynomials

This is the first of three volumes that form the Encyclopedia of Special Functions, an extensive update of the Bateman Manuscript Project. Volume 1 contains most of the material on orthogonal polynomials, from the classical orthogonal polynomials of Hermite, Laguerre and Jacobi to the Askey–Wilson polynomials, which are the most general basic hypergeometric orthogonal polynomials. Separate chapter

N-terminal acetylation of superoxide dismutase 1 accelerates amyloid formation without general destabilization of the apo state

Co- and post-translational modifications can significantly impact the structure, dynamics, and function of proteins. In this study, we investigate how N-terminal acetylation affects misfolding and self-assembly of the enzyme superoxide dismutase 1 (SOD1), implicated in amyotrophic lateral sclerosis (ALS). Studies of protein inclusions in patient samples and animal models have shown that wild-type

A systematic review and meta-analysis of real-world data predictors for conversion to progressive multiple sclerosis

Background: Available fluid biomarkers, neuroimaging techniques, and clinical assessments may enhance prediction of conversion to secondary progressive multiple sclerosis (SPMS). Objectives: : To identify robust real-world predictors of MS progression in the literature. Methods: : A systematic review was conducted in EMBASE. A total of 20,338 MS patients from 64 eligible studies were included. A p

Heparan sulfate N-deacetylase/N-sulfotransferase-1 regulates glioblastoma cell migration and invasion

The glioblastoma (GBM) microenvironment undergoes adaptations to support tumor progression, including a dysregulated extracellular matrix, with altered heparan sulfate (HS) proteoglycans. We investigated N-deacetylase/N-sulfotransferase-1 (NDST1) because NDSTs are initial modifying enzymes of HS biosynthesis and have key roles in designing the HS sulfation pattern. This, in turn governs interactio

Finite gap Jacobi matrices, I. The isospectral torus

Let e ⊂ ℝ be a finite union of disjoint closed intervals. In the study of orthogonal polynomials on the real line with measures whose essential support is e, a fundamental role is played by the isospectral torus. In this paper, we use a covering map formalism to define and study this isospectral torus. Our goal is to make a coherent presentation of properties and bounds for this special class as a

Optimal mechanical alloying and spark plasma sintering technique to obtain nanocrystallinity, minimal contamination and enhanced oxidation behaviour in AlCoCrFeNi high entropy alloys

The effect of the phase constitution of BCC/B2, FCC, Cr7C3 and their microstructural attributes are conspicuous on the hardness properties of AlCoCrFeNi HEAs [1]. The correlation of unsolicited C and O contaminant with process parameters (milling duration/rpm) and process control agent (PCA) categorically established that contamination increases with duration of mechanical alloying (MA) [2] . It i

Design Space Exploration and PPA Evaluation of ARM NI-700 Interconnect as a Replacement for NIC-400 in ASIC Architectures

With the rapid evolution of semiconductor technology and the growing demand for high-performance, low-power System-on-Chip solutions, the design of efficient and scalable on-chip interconnect architectures has become a critical challenge in modern ASIC development. This thesis focuses on design space exploration of replacing multiple ARM CoreLink NIC-400 crossbar-based interconnects with a unified