6 resultados para Agricultural laws and legislation
em University of Queensland eSpace - Australia
Resumo:
Objective: To test the hypothesis that the presence of national mental health policies, programs and legislation would be associated with lower national suicide rates. Method: Suicide rates from 100 countries were regressed on mental health policy, program and legislation indicators. Results: Contrary to the hypothesized relationship, the study found that after introducing mental health initiatives (with the exception of substance abuse policies), countries' suicide rates rose. Conclusion: It is of concern that most mental health initiatives are associated with an increase in suicide rates. However, there may be acceptable reasons for the observed findings, for example initiatives may have been introduced in areas of increasing need, or a case-finding effect may be operating. Data limitations must also be considered.
Dual-symmetric Lagrangians in quantum electrodynamics: I. Conservation laws and multi-polar coupling
Resumo:
By using a complex field with a symmetric combination of electric and magnetic fields, a first-order covariant Lagrangian for Maxwell's equations is obtained, similar to the Lagrangian for the Dirac equation. This leads to a dual-symmetric quantum electrodynamic theory with an infinite set of local conservation laws. The dual symmetry is shown to correspond to a helical phase, conjugate to the conserved helicity. There is also a scaling symmetry, conjugate to the conserved entanglement. The results include a novel form of the photonic wavefunction, with a well-defined helicity number operator conjugate to the chiral phase, related to the fundamental dual symmetry. Interactions with charged particles can also be included. Transformations from minimal coupling to multi-polar or more general forms of coupling are particularly straightforward using this technique. The dual-symmetric version of quantum electrodynamics derived here has potential applications to nonlinear quantum optics and cavity quantum electrodynamics.