417 research outputs found
Barriers to better care for people with AIDS in developing countries
Access to good quality antiretroviral treatment has
transformed the prognosis for people with AIDS in the
developed world. Although it is feasible and desirable
to deliver antiretroviral drugs in resource poor
settings,few of the 95% of people with HIV and
AIDS who live in developing countries receive them.
The World Health Organization has launched a
programme to deliver antiretroviral drugs to three million
people with AIDS in the developing world by
2005, the “3 by 5” initiative. We identify some of the
challenges faced by the initiative, focusing on delivery
of care
Introduction au dossier "L'éthique en anthropologie de la santé : conflits, pratiques, valeur heuristique"
Les femmes africaines face à l'épidémie de sida
En Afrique, les femmes sont plus nombreuses que les hommes à être infectées par le virus du sida. Plus vulnérables biologiquement, elles n’ont pas toujours la capacité de négocier qui leur permettrait d’insister sur l’utilisation de préservatifs ou sur la fidélité de leur partenaire. Prévention et dépistage, encore rares, leur sont cependant plus accessibles qu’aux hommes grâce aux consultations prénatales. Mais, si elles apprennent qu’elles sont infectées, leur fragilité socio-économique, la peur de l’opprobre et la pression de procréation qu’elles subissent, conduisent trois femmes sur quatre à taire leur séropositivité. Paradoxalement, elles bénéficient pourtant plus souvent que les hommes des traitements
Relativistic calculations of pionic and kaonic atoms hyperfine structure
We present the relativistic calculation of the hyperfine structure in pionic
and kaonic atoms. A perturbation method has been applied to the Klein-Gordon
equation to take into account the relativistic corrections. The perturbation
operator has been obtained \textit{via} a multipole expansion of the nuclear
electromagnetic potential. The hyperfine structure of pionic and kaonic atoms
provide an additional term in the quantum electrodynamics calculation of the
energy transition of these systems. Such a correction is required for a recent
measurement of the pion mass
Dielectronic Resonance Method for Measuring Isotope Shifts
Longstanding problems in the comparison of very accurate hyperfine-shift
measurements to theory were partly overcome by precise measurements on
few-electron highly-charged ions. Still the agreement between theory and
experiment is unsatisfactory. In this paper, we present a radically new way of
precisely measuring hyperfine shifts, and demonstrate its effectiveness in the
case of the hyperfine shift of and in
. It is based on the precise detection of dielectronic
resonances that occur in electron-ion recombination at very low energy. This
allows us to determine the hyperfine constant to around 0.6 meV accuracy which
is on the order of 10%
Associations between mode of HIV testing and consent, confidentiality, and referral: a comparative analysis in four African countries
Women's views on consent, counseling and confidentiality in PMTCT: a mixed-methods study in four African countries
Tensorial form and matrix elements of the relativistic nuclear recoil operator
Within the lowest-order relativistic approximation () and to
first order in , the tensorial form of the relativistic corrections of
the nuclear recoil Hamiltonian is derived, opening interesting perspectives for
calculating isotope shifts in the multiconfiguration Dirac-Hartree-Fock
framework. Their calculation is illustrated for selected Li-, B- and C-like
ions. The present work underlines the fact that the relativistic corrections to
the nuclear recoil are definitively necessary for getting reliable isotope
shift values.Comment: 22 pages, no figures, submitted to J. Phys.
Recommended from our members
Theory of Hyperfine Anomalies in Muonic Atoms
Negative muon spin precession experiments by Yamazaki, et al. have found giant hyperfine anomalies in muonic atoms ranging from a few percent up to 36%. In order to understand their results, we present Breit interaction calculations based on atomic self-consistent unrestricted Dirac-Fock solutions which explicitly include all electrons and the negative muon. The Breit interaction results (including the relativistic correction for the bound muon g-factor), vary from near zero for ..mu../sup -/ O/N to -5% for ..mu../sup -/Pd/Rh; this latter is much larger than the calculated muonic or nuclear Bohr-Weisskopf anomalies and much smaller than the 36% measured value. For ..mu../sup -/Ni/Co we find a calculated range of results (depending on assumed electronic configurations) of -2.3 to -2.7% in excellent agreement with recent measurements of the Yamazaki group. This excellent agreement in ..mu../sup -/Ni/Co provides strong support for the earlier suggestions that the discrepancy in the case of ..mu../sup -/Pd/Rh is due to experimental factors
Coordinate-space approach to the bound-electron self-energy: Self-Energy screening calculation
The self-energy screening correction is evaluated in a model in which the
effect of the screening electron is represented as a first-order perturbation
of the self energy by an effective potential. The effective potential is the
Coulomb potential of the spherically averaged charge density of the screening
electron. We evaluate the energy shift due to a , ,
, or electron screening a , ,
, or electron, for nuclear charge Z in the range . A detailed comparison with other calculations is made.Comment: 54 pages, 10 figures, 4 table
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