Search results for "Schwartz"

Maniobra de Schwartz

2010

Maniobra de Schwartz o prueba de percusión como prueba funcional en la valoración del sistema venoso.

Perlecan Maintains the Integrity of Cartilage and Some Basement Membranes

1999

Perlecan is a heparan sulfate proteoglycan that is expressed in all basement membranes (BMs), in cartilage, and several other mesenchymal tissues during development. Perlecan binds growth factors and interacts with various extracellular matrix proteins and cell adhesion molecules. Homozygous mice with a null mutation in the perlecan gene exhibit normal formation of BMs. However, BMs deteriorate in regions with increased mechanical stress such as the contracting myocardium and the expanding brain vesicles showing that perlecan is crucial for maintaining BM integrity. As a consequence, small clefts are formed in the cardiac muscle leading to blood leakage into the pericardial cavity and an ar…

Spectrum of composition operators on S(R) with polynomial symbols

2020

Abstract We study the spectrum of operators in the Schwartz space of rapidly decreasing functions which associate each function with its composition with a polynomial. In the case where this operator is mean ergodic we prove that its spectrum reduces to {0}, while the spectrum of any non mean ergodic composition operator with a polynomial always contains the closed unit disc except perhaps the origin. We obtain a complete description of the spectrum of the composition operator with a quadratic polynomial or a cubic polynomial with positive leading coefficient.

Partial Multiplication of Operators in Rigged Hilbert Spaces

2005

The problem of the multiplication of operators acting in rigged Hilbert spaces is considered. This is done, as usual, by constructing certain intermediate spaces through which the product can be factorized. In the special case where the starting space is the set of C∞-vectors of a self-adjoint operator A, a general procedure for constructing a special family of interspaces is given. Their definition closely reminds that of the Bessel potential spaces, to which they reduce when the starting space is the Schwartz space \(\mathcal{S}(\mathbb{R}^n ).\) Some applications are considered.

Biweights on Partial *-Algebras

2000

This chapter is devoted to the systematic investigation of biweights on partial *-algebras. These are a generalization of invariant positive sesquilinear forms that still allows a Gel’fand—Naĭmark—Segal (GNS) construction of representations. In Section 9.1, we apply this GNS construction for biweights and we obtain *-representations and cyclic vector representations of partial *-algebras, and we give some examples of biweights. Section 9.2 is devoted to the investigation of the Radon—Nikodým theorem and the Lebesgue decomposition theorem for biweights on partial *-algebras. In Section 9.3, we define regular and singular biweights on partial *-algebras and we characterize them with help of t…

ANALISI SISTEMATICA DELL'UNIVERSO VALORIALE DEI GIOVANI ATTRAVERSO LO SCHWARTZ VALUES SURVEY (SVS)

2007

The aim of this research is inquiring how the universal human values proposed by Schwartz are applicable to a sample of Sicilian young people. Particularly, our research wants to evaluate how much our value system is afar from the one proposed by Schwartz and to which values our sample gives importance. The results of the research seem to confirm Schwartz’s theory on human values, except some difference.

A note on the Schwartz space ?(? n ) endowed with the strict topology

1990

Universalisti vai suoriutuja : suomalaisten jakautuminen Shalon Schwartzin arvotypologiaan sosiodemografisten taustamuuttujien valossa

2015

Tutkimuksen tehtävänä on selvittää kuinka suomalaiset jakautuvat sosiodemografisten taustamuuttujien mukaan sosiaalipsykologi ja arvotutkija Shalom Schwartzin kymmmenen arvon arvotypologiaan. Sosiodemografisina taustamuuttujina tutkimuksessa ovat mm. ikä, sukupuoli, tulotaso sekä työantajasektori. Tarkoituksena on tarkastella vaikuttavatko nämä sosiodemografiset taustamuuttujat siihen millaisiin arvoihin suomalaiset samaistuvat. Aihe on sosiologisesti tärkeä ja relevantti, sillä viime vuosina valtamediassa yleistynyt keskustelu arvojen kovenemisesta, katoamisesta tai vääristymisestä viestii siitä, että jotain muutosta on tapahtumassa yhteiskunnassa. Arvoja tutkimalla tuotetaan tarkkaa tieto…

Dynamics and spectra of composition operators on the Schwartz space

2017

[EN] In this paper we study the dynamics of the composition operators defined in the Schwartz space of rapidly decreasing functions. We prove that such an operator is never supercyclic and, for monotonic symbols, it is power bounded only in trivial cases. For a polynomial symbol ¿ of degree greater than one we show that the operator is mean ergodic if and only if it is power bounded and this is the case when ¿ has even degree and lacks fixed points. We also discuss the spectrum of composition operators.

Composition operators on the Schwartz space

2018

[EN] We study composition operators on the Schwartz space of rapidly decreasing functions. We prove that such a composition operator is never a compact operator and we obtain necessary or sufficient conditions for the range of the composition operator to be closed. These conditions are expressed in terms of multipliers for the Schwartz class and the closed range property of the corresponding operator considered in the space of smooth functions.