1,113 research outputs found
Universal health care and equity: evidence of maternal health based on an analysis of demographic and household survey data
INTRODUCTION: The drive toward universal health coverage (UHC) is central to the post 2015 agenda, and is incorporated as a target in the new Sustainable Development Goals. However, it is recognised that an equity dimension needs to be included when progress to this goal is monitored. WHO have developed a monitoring framework which proposes a target of 80 % coverage for all populations regardless of income and place of residence by 2030, and this paper examines the feasibility of this target in relation to antenatal care and skilled care at delivery.METHODOLOGY: We analyse the coverage gap between the poorest and richest groups within the population for antenatal care and presence of a skilled attendant at birth for countries grouped by overall coverage of each maternal health service. Average annual rates of improvement needed for each grouping (disaggregated by wealth quintile and urban/rural residence) to reach the goal are also calculated, alongside rates of progress over the past decades for comparative purposes.FINDINGS: Marked inequities are seen in all groups except in countries where overall coverage is high. As the monitoring framework has an absolute target countries with currently very low coverage are required to make rapid and sustained progress, in particular for the poorest and those living in rural areas. The rate of past progress will need to be accelerated markedly in most countries if the target is to be achieved, although several countries have demonstrated the rate of progress required is feasible both for the population as a whole and for the poorest.CONCLUSIONS: For countries with currently low coverage the target of 80 % essential coverage for all populations will be challenging. Lessons should be drawn from countries who have achieved rapid and equitable progress in the past.<br/
Non-vanishing Magnetic Flux through the Slightly-charged Kerr Black Hole
In association with the Blanford-Znajek mechanism for rotational energy
extraction from Kerr black holes, it is of some interest to explore how much of
magnetic flux can actually penetrate the horizon at least in idealized
situations. For completely uncharged Kerr hole case, it has been known for some
time that the magnetic flux gets entirely expelled when the hole is
maximally-rotating. In the mean time, it is known that when the rotating hole
is immersed in an originally uniform magnetic field surrounded by an ionized
interstellar medium (plasma), which is a more realistic situation, the hole
accretes certain amount of electric charge. In the present work, it is
demonstrated that as a result of this accretion charge small enough not to
disturb the geometry, the magnetic flux through this slightly charged Kerr hole
depends not only on the hole's angular momentum but on the hole's charge as
well such that it never vanishes for any value of the hole's angular momentum.Comment: 33pages, 1 figure, Revtex, some comments added, typos correcte
Administration of human chorionic gonadotropin at embryo transfer induced ovulation of a first-wave dominant follicle and increased progesterone and transfer pregnancy rates
Beef Cattle Research, 2011 is known as Cattlemen’s Day, 2011Embryo transfer (ET) has become more widespread in recent years as a way to improve
cattle genetics. According to the annual statistical survey of the American Embryo
Transfer Association, more than 200,000 fresh and frozen bovine embryos were
transferred in 2008. But despite advancements in reproductive technologies that have
occurred since ET was commercialized in the 1970s, industrywide pregnancy rates are
only 62.4 and 56.9% for fresh and frozen-thawed ET, respectively. Using ET helps
avoid problems from failed fertilization; however, fertilization failure has been characterized
as a relatively unimportant factor of pregnancy loss. Approximately 10% of pregnancy
failures resulted from fertilization failure and another 10% from failed embryo
development. Approximately 20 to 25% of the pregnancy loss in an ET program could
be characterized as early embryonic loss
Hagedorn transition and chronology protection in string theory
We conjecture chronology is protected in string theory due to the
condensation of light winding strings near closed null curves. This
condensation triggers a Hagedorn phase transition, whose end-point target space
geometry should be chronological. Contrary to conventional arguments,
chronology is protected by an infrared effect. We support this conjecture by
studying strings in the O-plane orbifold, where we show that some winding
string states are unstable and condense in the non-causal region of spacetime.
The one-loop string partition function has infrared divergences associated to
the condensation of these states.Comment: 40 pages, 11 figures. Expanded discussion on evolution of on-shell
modes and added appendi
Particle Motion and Electromagnetic Fields of Rotating Compact Gravitating Objects with Gravitomagnetic Charge
The exact solution for the electromagnetic field occuring when the
Kerr-Taub-NUT compact object is immersed (i) in an originally uniform magnetic
field aligned along the axis of axial symmetry (ii) in dipolar magnetic field
generated by current loop has been investigated. Effective potential of motion
of charged test particle around Kerr-Taub-NUT gravitational source immersed in
magnetic field with different values of external magnetic field and NUT
parameter has been also investigated. In both cases presence of NUT parameter
and magnetic field shifts stable circular orbits in the direction of the
central gravitating object. Finally we find analytical solutions of Maxwell
equations in the external background spacetime of a slowly rotating magnetized
NUT star. The star is considered isolated and in vacuum, with monopolar
configuration model for the stellar magnetic field.Comment: 18 pages, 6 figures, new results in section 2 added, section 3 is
revised, 3 references are adde
Five Dimensional Rotating Black Hole in a Uniform Magnetic Field. The Gyromagnetic Ratio
In four dimensional general relativity, the fact that a Killing vector in a
vacuum spacetime serves as a vector potential for a test Maxwell field provides
one with an elegant way of describing the behaviour of electromagnetic fields
near a rotating Kerr black hole immersed in a uniform magnetic field. We use a
similar approach to examine the case of a five dimensional rotating black hole
placed in a uniform magnetic field of configuration with bi-azimuthal symmetry,
that is aligned with the angular momenta of the Myers-Perry spacetime. Assuming
that the black hole may also possess a small electric charge we construct the
5-vector potential of the electromagnetic field in the Myers-Perry metric using
its three commuting Killing vector fields. We show that, like its four
dimensional counterparts, the five dimensional Myers-Perry black hole rotating
in a uniform magnetic field produces an inductive potential difference between
the event horizon and an infinitely distant surface. This potential difference
is determined by a superposition of two independent Coulomb fields consistent
with the two angular momenta of the black hole and two nonvanishing components
of the magnetic field. We also show that a weakly charged rotating black hole
in five dimensions possesses two independent magnetic dipole moments specified
in terms of its electric charge, mass, and angular momentum parameters. We
prove that a five dimensional weakly charged Myers-Perry black hole must have
the value of the gyromagnetic ratio g=3.Comment: 23 pages, REVTEX, v2: Minor changes, v3: Minor change
Wavy Strings: Black or Bright?
Recent developments in string theory have brought forth a considerable
interest in time-dependent hair on extended objects. This novel new hair is
typically characterized by a wave profile along the horizon and angular
momentum quantum numbers in the transverse space. In this work, we
present an extensive treatment of such oscillating black objects, focusing on
their geometric properties. We first give a theorem of purely geometric nature,
stating that such wavy hair cannot be detected by any scalar invariant built
out of the curvature and/or matter fields. However, we show that the tidal
forces detected by an infalling observer diverge at the `horizon' of a black
string superposed with a vibration in any mode with . The same
argument applied to longitudinal () waves detects only finite tidal
forces. We also provide an example with a manifestly smooth metric, proving
that at least a certain class of these longitudinal waves have regular
horizons.Comment: 45 pages, latex, no figure
The acceleration of the universe and the physics behind it
Using a general classification of dark enegy models in four classes, we
discuss the complementarity of cosmological observations to tackle down the
physics beyond the acceleration of our universe. We discuss the tests
distinguishing the four classes and then focus on the dynamics of the
perturbations in the Newtonian regime. We also exhibit explicitely models that
have identical predictions for a subset of observations.Comment: 18 pages, 18 figure
The role of a disulfide bridge in the stability and folding kinetics of Arabidopsis thaliana cytochrome c6A
Cytochrome c 6A is a eukaryotic member of the Class I cytochrome c family possessing a high structural homology with photosynthetic cytochrome c 6 from cyanobacteria, but structurally and functionally distinct through the presence of a disulfide bond and a heme mid-point redox potential of + 71 mV (vs normal hydrogen electrode). The disulfide bond is part of a loop insertion peptide that forms a cap-like structure on top of the core α-helical fold. We have investigated the contribution of the disulfide bond to thermodynamic stability and (un)folding kinetics in cytochrome c 6A from Arabidopsis thaliana by making comparison with a photosynthetic cytochrome c 6 from Phormidium laminosum and through a mutant in which the Cys residues have been replaced with Ser residues (C67/73S). We find that the disulfide bond makes a significant contribution to overall stability in both the ferric and ferrous heme states. Both cytochromes c 6A and c 6 fold rapidly at neutral pH through an on-pathway intermediate. The unfolding rate for the C67/73S variant is significantly increased indicating that the formation of this region occurs late in the folding pathway. We conclude that the disulfide bridge in cytochrome c 6A acts as a conformational restraint in both the folding intermediate and native state of the protein and that it likely serves a structural rather than a previously proposed catalytic role. © 2011 Elsevier B.V. All rights reserved
Orbital state and magnetic properties of LiV_2 O_4
LiV_2 O_4 is one of the most puzzling compounds among transition metal oxides
because of its heavy fermion like behavior at low temperatures. In this paper
we present results for the orbital state and magnetic properties of LiV_2 O_4
obtained from a combination of density functional theory within the local
density approximation and dynamical mean-field theory (DMFT). The DMFT
equations are solved by quantum Monte Carlo simulations. The trigonal crystal
field splits the V 3d orbitals such that the a_{1g} and e_{g}^{pi} orbitals
cross the Fermi level, with the former being slightly lower in energy and
narrower in bandwidth. In this situation, the d-d Coulomb interaction leads to
an almost localization of one electron per V ion in the a_{1g} orbital, while
the e_{g}^{pi} orbitals form relatively broad bands with 1/8 filling. 2The
theoretical high-temperature paramagnetic susceptibility chi(T) follows a
Curie-Weiss law with an effective paramagnetic moment p_{eff}=1.65 in agreement
with the experimental results.Comment: 11 pages, 10 figures, 2 table
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