7,270 research outputs found
Perceived motor ability and selection, optimization, and compensation: Effects of age and institutionalization
The authors examined the mediation effect of the perceived motor ability (PMA) on the
direct “effects” of age (third vs. fourth age) and residential status (institutionalized vs.
communitarians) on selection, optimization, and compensation (SOC) strategies. With a
non-probabilistic sample of 107 elders (Mdn = 80 years) from urban areas, and
controlled for cognitive impairment and depression, the authors analysed the structural
component of the path model with latent constructs that represents those relationships.
This was made only after the structural validity of the constructs had been assured.
Constructs were operationalized through the PMA questionnaire and a 16-item version
of the SOC questionnaire. Only age had direct effects on the constructs: lower PMA and
lower SOC of the elders in the fourth age. Authors also verified that the PMA mediation
effect was partial
Nonperturbative Aspects of the two-dimensional Massive Gauged Thirring Model
In this paper we present a study based on the use of functional techniques on
the issue of insertions of massive fermionic fields in the two-dimensional
massless Gauged Thirring Model. As it will be shown, the fermionic mass
contributes to the Green's functions in a surprisingly simple way, leaving
therefore the original nonperturbative nature of the massless results still
intact in the massive theory. Also, by means of complementarity, we present a
second discussion of the massive model, now at its bosonic representation.Comment: 18 pages, to appear at Int. J. Mod. Phys.
Path-ordered Phase Factors in Scalar Quantum Electrodynamics
Starting from linear equations for the complex scalar field, the two- and
three-point Green's functions are obtained in the infrared approximation. We
show that the infrared singularity factorizes in the vertex function as in
spinorial QED, reproducing in a straightforward way the result of lenghty
perturbative calculations.Comment: 11 pages, LaTe
What's Wrong with Pauli-Villars Regularization in ?
In this letter we argue that there is no ambiguity between the Pauli-Villars
and other methods of regularization in (2+1)-dimensional quantum
electrodynamics with respect to dynamical mass generation, provided we properly
choose the couplings for the regulators.Comment: 07 pages, Latex, no figure
Equivalence of Many-Gluon Green Functions in Duffin-Kemmer-Petieu and Klein-Gordon-Fock Statistical Quantum Field Theories
We prove the equivalence of many-gluon Green functions in
Duffin-Kemmer-Petieu and Klein-Gordon-Fock statistical quantum field theories.
The proof is based on the functional integral formulation for the statistical
generating functional in a finite-temperature quantum field theory. As an
illustration, we calculate one-loop polarization operators in both theories and
show that their expressions indeed coincide.Comment: 8 page
- …