1,073 research outputs found
The Self-Force of a Charged Particle in Classical Electrodynamics with a Cut-off
We discuss, in the context of classical electrodynamics with a Lorentz
invariant cut-off at short distances, the self-force acting on a point charged
particle. It follows that the electromagnetic mass of the point charge occurs
in the equation of motion in a form consistent with special relativity. We find
that the exact equation of motion does not exhibit runaway solutions or
non-causal behavior, when the cut-off is larger than half of the classical
radius of the electron.Comment: 17 pages, 1 figur
Signatures of Confinement in Axial Gauge QCD
A comparative dynamical study of axial gauge QED and QCD is presented.
Elementary excitations associated with particular field configurations are
investigated. Gluonic excitations analogous to linearly polarized photons are
shown to acquire infinite energy. Suppression of this class of excitations in
QCD results from quantization of the chromelectric flux and is interpreted as a
dual Meissner effect, i.e. as expulsion from the QCD vacuum of chromo-electric
fields which are constant over significant distances. This interpretation is
supported by a comparative evaluation of the interaction energy of static
charges in the axial gauge representation of QED and QCD.Comment: 22 pages (no figures
Correlation Effects in Nuclear Transparency
The Glauber approximation is used to calculate the contribution of nucleon
correlations in high-energy reactions. When the excitation energy of
the residual nucleus is small, the increase of the nuclear transparency due to
correlations between the struck nucleon and the other nucleons is mostly
compensated by a decrease of the transparency due to the correlations between
non detected nucleons. We derive Glauber model predictions for nuclear
transparency for the differential cross section when nuclear shell level
excitations are measured. The role of correlations in color transparency is
briefly discussed.Comment: 24 pages revtex, 4 uuencoded PostScript Figures as separate fil
a business centered approach
This thesis aims at exploring the benefits regarding the adoption of nonadjudicative
alternative means of dispute resolution (NAADR), mediation in specific, in
corporation’s legal frameworks and contracts. This paper reviews literature, categorizes
the types of corporate governance conflicts, analyses several studies and presents
empirical evidence that shows the positive effects of a NAADR as an enhancing factor
in increasing the value of a company.
This paper starts by acknowledging the existence of several situations in
corporate governance that are commonly identified as irritants for a healthy steering of a
company. We can separate these situations causing conflict in two different groups: the
conflicts that are board-related and the ones that are corporate governance related
conflicts, without needing the presence of the board.
The categorization of corporate governance conflicts is followed by an overview
of the negative consequences that these conflicts have for the overall performance of a
company. It finds, supported on evidence presented, that corporate governance conflicts,
on an economic stand point, contribute to undermine a company´s overall performance
by making it less profitable, leading inclusively to shareholder value decline.
This shareholder decline claim is illustrated by recent two different corporate
scandals: The general motors case and the Volkswagen emission case. In both cases,
decline in shareholder value happened after public disclosure of information. It
continues by building on existence research that analyses the relation between a
Director resignation that triggers the necessity of filling the 8-K filling form, and the
reaction of the market that followed such happening. It follows, by presenting the ADR
procedures continuum, highlighting, in specific the advantages of mediation and its importance on the prevention in what concerns the negatives outcomes resulted from
corporate governance conflicts.
It concludes by asserting that mediation is one of the best suited nonadjudicative
alternative means of dispute resolution for corporations. Nevertheless, it
acknowledges its lack of implementation on the corporate governance realm and
analyses the main reasons behind that lack of implementation, with a specific focus on
the Portuguese legal framework. It concludes that the legal Portuguese framework and
the Portuguese lawyer’s mindset doesn´t favor the implementation of mediation as a
true “forum” to seek grievance for the resolution of a conflict. This thesis ends by
providing a thorough analysis on the macro and micro economic benefits that result
from good corporate governance practices where NAADR mechanisms find its rightful
place as an enhancing factor for firm growth
Supersymmetric Quantization of Anisotropic Scalar-Tensor Cosmologies
In this paper we show that the spatially homogeneous Bianchi type I and
Kantowski-Sachs cosmologies derived from the Brans-Dicke theory of gravity
admit a supersymmetric extension at the quantum level. Global symmetries in the
effective one-dimensional actions characterize both classical and quantum
solutions. A wide family of exact wavefunctions satisfying the supersymmetric
constraints are found. A connection with quantum wormholes is briefly
discussed.Comment: In Press, Class. Quantum Grav. 20 pages, Late
A Posterior Interosseous Nerve Syndrome Associated With Spontaneous Rupture of the Extensor Pollicis Longus Tendon
Posterior interosseous nerve entrapment syndrome and spontaneous rupture of the extensor pollicis longus tendon are rare conditions. The authors describe the bizarre combination of a spontaneous rupture of the extensor pollicis longus tendon in a 82-year-old lady with a posterior interosseous nerve syndrome. As far as the authors know, this is the first description of such an association in the literature. Surgical exploration revealed compression of the posterior interosseous nerve at the proximal portion of the supinator muscle and at Henry's leash. The nerve was freed, and the tendon of the extensor index proprius was transferred to the extensor pollicis longus. Six months after the procedure, the patient had resumed her daily activities, showing a good functional result
Semiclassical approximation to supersymmetric quantum gravity
We develop a semiclassical approximation scheme for the constraint equations
of supersymmetric canonical quantum gravity. This is achieved by a
Born-Oppenheimer type of expansion, in analogy to the case of the usual
Wheeler-DeWitt equation. The formalism is only consistent if the states at each
order depend on the gravitino field. We recover at consecutive orders the
Hamilton-Jacobi equation, the functional Schrodinger equation, and quantum
gravitational correction terms to this Schrodinger equation. In particular, the
following consequences are found:
(i) the Hamilton-Jacobi equation and therefore the background spacetime must
involve the gravitino, (ii) a (many fingered) local time parameter has to be
present on (the space of all possible tetrad and gravitino
fields), (iii) quantum supersymmetric gravitational corrections affect the
evolution of the very early universe. The physical meaning of these equations
and results, in particular the similarities to and differences from the pure
bosonic case, are discussed.Comment: 34 pages, clarifications added, typos correcte
Improving quality of life for people with dementia in care homes: Making psychosocial interventions work
This is the author accepted manuscript. The final version is available from Cambridge University Press via the DOI in this recordPsychosocial interventions can improve behaviour and mood in people with dementia, but it is unclear how to maximise their effectiveness or acceptability in residential settings. Aims To understand what underlies the successful implementation of psychosocial interventions in care homes. Method Systematic review and meta-synthesis of qualitative research. Results The synthesis of 39 qualitative papers revealed that beneficial psychosocial interventions met the needs of people with dementia to connect with others, make a meaningful contribution and reminisce. Successful implementation rested on the active engagement of staff and family and the continuing provision of tailored interventions and support. This necessitated staff time, and raised issues around priorities and risk, but ultimately helped redefine staff attitudes towards residents and the caregiving role. Conclusions The findings from the meta-synthesis can help to inform the development and evaluation of psychosocial interventions in care homes and support their widespread implementation in clinical settings.National Institute for Health Research (NIHR
Estudo sobre os embargos de nulidade e infringentes do julgado previstos no cĂłdigo de processo civil
Tese (Catedra) - Faculdade de Direito da Universidade do ParanaInclui referĂŞncias e Ăndic
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