21,164 research outputs found
Potential impact of adjustment policies on vulnerability of women and children to HIV/AIDS in sub-Saharan Africa
This paper evaluates the potential impact of adjustment policies of the International Monetary Fund and the World Bank on the vulnerability of women and children to HIV/AIDS in sub-Saharan Africa. A conceptual framework, composed of five different pathways of causation, is used for the evaluation. These five pathways connect changes at the macro level (e.g. removal of food subsidies) with effects at the meso (e.g. higher food prices) and micro levels (e.g. exposure of women and children to commercial sex) that influence the vulnerability of women and children to HIV/AIDS. Published literature on adjustment policies and socioeconomic determinants of HIV/AIDS among women and children in sub-Saharan Africa was reviewed to explore the cause-effect relationships included in the theoretical framework. Evidence suggests that adjustment policies may inadvertently produce conditions facilitating the exposure of women and children to HIV/AIDS. Complex research designs are needed to further investigate this relationship. A shift in emphasis from an individual approach to a socioeconomic approach in the study of HIV infection among women and children in the developing world is suggested. Given the potential for adjustment policies to exacerbate the AIDS pandemic among women and children, a careful examination of the effects of these policies on maternal and child welfare is urgently needed
User fees impact access to healthcare for female children in rural Zambia
The World Bank and International Monetary Fund favor healthcare user fees. User fees offer revenue and may decrease inappropriate care. However, user fees may deter needed care, especially in vulnerable populations. A cross-sectional analysis of healthcare utilization in a large Zambian hospital was conducted for children 3-6 years of age during a 1-month observation period. Diagnoses and treatments were compared using paired t-tests. Chi-squared tests compared outpatient service use. The relative risk of admission was determined for each stratum. Logistic models were developed to evaluate the impact of age, gender, and the age-gender interaction on hospital admissions. Trends suggest female children may be less likely to present for care when user fees are imposed. However, treatment type, treatment number, and number of diagnoses did not differ between genders. The relative risk of admission was highest for males 5-6 years old. Neither age nor gender alone was a significant determinant of hospital admission. However, the age-gender interaction was significant with female admissions least likely when costs were incurred. We conclude that user fees appear to decrease differentially utilization of inpatient care for female children in rural Zambia
BPS black holes, the Hesse potential, and the topological string
The Hesse potential is constructed for a class of four-dimensional N=2
supersymmetric effective actions with S- and T-duality by performing the
relevant Legendre transform by iteration. It is a function of fields that
transform under duality according to an arithmetic subgroup of the classical
dualities reflecting the monodromies of the underlying string compactification.
These transformations are not subject to corrections, unlike the
transformations of the fields that appear in the effective action which are
affected by the presence of higher-derivative couplings. The class of actions
that are considered includes those of the FHSV and the STU model. We also
consider heterotic N=4 supersymmetric compactifications. The Hesse potential,
which is equal to the free energy function for BPS black holes, is manifestly
duality invariant. Generically it can be expanded in terms of powers of the
modulus that represents the inverse topological string coupling constant,
, and its complex conjugate. The terms depending holomorphically on
are expected to correspond to the topological string partition function and
this expectation is explicitly verified in two cases. Terms proportional to
mixed powers of and are in principle present.Comment: 28 pages, LaTeX, added comment
On perfect totient numbers
Let n > 2 be a positive integer and let φ denote Euler's totient function. Define φ1(n) = φ(n) and φk(n) = φ(φk-1(n)) for all integers k ≥ 2. Define the arithmetic function S by S(n) = φ(n) + φ2(n) +...+ φc(n) + 1, where φc(n) = 2. We say n is a perfect totient number if S(n) = n. We give a list of known perfect totient numbers, and we give sufficient conditions for the existence of further perfect totient numbers
Preferential expression of the transcription coactivator HTIF1alpha gene in acute myeloid leukemia and MDS-related AML
HTIF1α, a transcription coactivator which is able to mediate RARα activity and functionally interact with PML, is encoded by a gene on chromosome 7q32–34, which is a critical region in acute myeloid leukemias (AML). With the assumption that this gene may be related to AML, we investigated the HTIF1α DNA structure and RNA expression in leukemic cells from 36 M1–M5 AML patients (28 ‘de novo’ and eight ‘secondary’ to myelodysplastic syndrome (MDS)). Abnormal HTIF1α DNA fragments were never found, whereas loss of HTIF1α DNA was observed in the patients with chromosome 7q32 deletion and translocation, and in one case without detectable chromosome 7 abnormality. HTIF1α RNA was found in acute myelocytic leukemic blasts, and was almost undetectable in normal mononuclear cells. The expression varied among the patients: higher in M1 to M3 subtypes, with the highest values in M1; low levels were constantly observed in M4 and M5 AML. In addition, HTIF1α was significantly overexpressed in MDS-related AML (MDR-AML), but not in MDS. We also found that HTIF1α expression was high in myeloid cell lines. In myeloblastic HL60 and promyelocytic NB4 cells, induced to differentiate along the monocytic–macrophage pathway by TPA or vitamin D3, HTIF1α expression decreased, whereas it was maintained at high levels on induction to granulocytic differentiation by RA or DMSO. In K562 cells, HTIF1α RNA levels did not change after hemin-induced erythroid differentiation. These results suggest that HTIF1α could play a role in myeloid differentiation, being distinctly regulated in hematopoietic lineages
Hybrid fuel cell-based energy system with metal hydride hydrogen storage for small mobile applications
This paper describes the general architecture of a hybrid energy system, whose main components are a proton exchange membrane fuel cell, a battery pack and an ultracapacitor pack as power sources, and metal hydride canisters as energy storage devices, suitable for supplying power to small mobile non-automotive devices in a flexible and variable way. The first experimental results carried out on a system prototype are described, showing that the extra components, required in order to manage the hybrid system, do not remarkably affect the overall system efficiency, which is always higher than 36% in all the test configurations examined. in fact, the system allows the fuel cell to work most often at quasi-optimal conditions, near its maximum efficiency (i.e. at low/medium loads), because high external loads are met by the combined effort of the fuel cell and the ultracapacitors. For the same reason, the metal hydride storage system can be used also under highly dynamic operating conditions, notwithstanding its usually poor kinetic performance. (C) 2009 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved
Triboson interpretations of the ATLAS diboson excess
The ATLAS excess in fat jet pair production is kinematically compatible with
the decay of a heavy resonance into two gauge bosons plus an extra particle.
This hypothesis would explain the absence of such a large excess in the
analogous CMS analysis of fat dijet final states, as well as the negative
results of diboson resonance searches in the semi-leptonic decay modes. If the
extra particle is the Higgs boson, this hypothesis might also explain
-statistical fluctuations aside- why the CMS search for WH resonances in the
semi-leptonic channel finds some excess while in the fully hadronic one it does
not have a significant deviation.Comment: LaTeX 17 pages. v2: Enlarged discussion to address CMS WH excess. v3:
Added discussion of diboson helicities. Final version to appear in JHE
Using New Submillimetre Surveys to Identify the Evolutionary Status of High-z Galaxies
This paper describes a key submillimetre survey which we are currently
conducting to address some of the outstanding questions in cosmology - how, at
what epoch and over what period of time did massive galaxies form at high
redshift? A summary of the technical feasibility of future submillimetre
observations with new ground-based, airborne and satellite telescopes is also
presented.Comment: 6 pages, 3 postscript figures, LaTex uses Kluwer book style file
crckapb10.sty, to appear in "Observational Cosmology with the New Radio
Surveys", 13-15 January 1997, Puerto de la Cruz, Tenerife, M.Bremer,
N.Jackson, I.Perez-Fournon (eds.), Kluwe
On the quantification of intertest variability in ecotoxicity data with application to species sensitivity distributions
Ecotoxicological hazard assessment relies on species effect data to estimate quantities such as the predicted no-effect concentration. While there is a concerted effort to quantify uncertainty in risk assessments, the uncertainty due to intertest variability in species effect measurements is an overlooked component. The European Union Registration, Evaluation, Authorisation, and Restriction of Chemicals (REACH) guidance document suggests that multiple toxicity records for a given chemical–species combination should be aggregated by the geometric mean. Ignoring this issue or applying unjustified so-called harmonization methods weakens the defensibility of uncertainty quantification and interpretation about properties of ecological models, for example, the predicted no-effect concentration. In the present study, the authors propose a simple and broadly theoretically justifiable model to quantify intertest variability and analyze it using Bayesian methods. The value of data in ecotoxicity databases is maximized by using (interval-)censored data. An exploratory analysis is provided to support the model. The authors conclude, based on a large ecotoxicity database of acute effects to aquatic species, that the standard deviation of intertest variability is approximately a factor (or fold-difference) of 3. The consequences for decision makers of (not) adjusting for intertest variability are demonstrated. Environ. Toxicol. Chem. 2012; 31: 1903–1910. © 2012 SETA
Medical students from Parakou (Benin) and West-African traditional beliefs on death and cadavers
No Abstrac
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