Infant feeding choices practiced among HIV positive mothers attending a prevention of mother to child transmission (PMTCT) of HIV Program in Nnewi, Nigeria

Background: The HIV epidemic has significantly altered the context within which women make decisions about how they will feed their infants. This study examined the antenatal infant feeding choices and actual infant feeding practices of HIV-positive mothers in order to assess adherence to the 2010 WHO national infant feeding guidelines in Nnewi, Nigeria. Methods: The study was conducted between January 2012 and February 2013 at Nnamdi-Azikiwe University Teaching Hospital (NAUTH) in Nnewi-Anambra State, Nigeria. It was a prospective cohort study of HIV positive women attending the Prevention of Mother-To-Child Transmission (PMTCT) clinic in NAUTH. Women received HIV Counseling and Testing (HCT) from trained HIV positive women working in the hospital and from members of HIV support groups. The women made an informed decision on their infant feeding choice and received antiretroviral (ARV) treatment or prophylaxis (WHO option B) following WHO 2010 guidelines. Each mother-baby pair was followed up until the HIV sero-status of the baby was determined by DNA PCR (6-8weeks after cessation of breastfeeding). Results: The overall HIV MTCT rate was 19 of 583 (3.3%; 95% confidence interval (CI): 2.0 - 5.0). Only 94 (16.1%; 95% CI: 13.2 - 19.4) mothers complied with the WHO 2010 recommendation of exclusive breastfeeding (EBF) and ARV treatment or prophylaxis. Overall, 431 (73.9%) mother-baby pairs received prophylactic ARV intervention; in 88 (15.1%) pairs, the baby or the mother received ARV; while in 64 (11.0%) pairs, neither mother nor baby received ARV. When the mother-baby pair received ARV, MTCT was 0.8%, 1.7% and 5.9% for Exclusive Formular Feeding (EFF), EBF and Mixed Feeding (MF), respectively. When either mother or baby received intervention, MTCT rates increased to 3.3%, 4.8% and 7.7% for EFF, EBF and MF, respectively. The rate of MTCT was further increased to 5.1%, 6.7% and 23.5% when neither mother nor baby received intervention for EFF, EBF and MF respectively. Conclusion: EFF is still the infant feeding option preferred and practiced by majority of our HIV positive mothers despite the promotion of the safety of EBF with ARV interventions according to WHO 2010 guideline. It will take some time to change existing belief in EFF for us to achieve the required shift to EBF in our practice area. We also demonstrated that ARV treatment/chemoprophylaxis for both mother and baby is an important measure for achieving the reduction of MTCT of HIV in breastfeeding setting mixed feeding practice is associated with an increased rate of MTCT and should be strongly discouraged. Increasing the uptake of ARV treatment/ chemoprophylaxis and ensuring appropriate counseling about infant feeding practices have the potential to markedly decrease the rate of MTCT of HIV in developing countries

Modelling the role of groundwater hydro-refugia in East African hominin evolution and dispersal.

Water is a fundamental resource, yet its spatiotemporal availability in East Africa is poorly understood. This is the area where most hominin first occurrences are located, and consequently the potential role of water in hominin evolution and dispersal remains unresolved. Here, we show that hundreds of springs currently distributed across East Africa could function as persistent groundwater hydro-refugia through orbital-scale climate cycles. Groundwater buffers climate variability according to spatially variable groundwater response times determined by geology and topography. Using an agent-based model, grounded on the present day landscape, we show that groundwater availability would have been critical to supporting isolated networks of hydro-refugia during dry periods when potable surface water was scarce. This may have facilitated unexpected variations in isolation and dispersal of hominin populations in the past. Our results therefore provide a new environmental framework in which to understand how patterns of taxonomic diversity in hominins may have developed

Effect of polycrystallinity on the optical properties of highly oriented ZnO grown by pulsed laser deposition

We report the results of photoluminescence and reflectance measurements on highly c-axis oriented polycrystalline ZnO grown by pulsed laser deposition. The samples measured were grown under identical conditions and were annealed in-situ at various temperatures for 10-15 min. The band-edge photoluminescence spectra of the material altered considerably with an increase in grain size, with increased free exciton emission and observable excitonic structure in the reflectance spectra. The green band emission also increased with increasing grain size. A deformation potential analysis of the effect of strain on the exciton energy positions of the A- and B-excitons demonstrated that the experimental exciton energies could not be explained solely in terms of sample strain. We propose that electric fields in the samples due to charge trapping at grain boundaries are responsible for the additional perturbation of the excitons. This interpretation is supported by theoretical estimates of the exciton energy perturbation due to electric fields. The behaviour of the green band in the samples provides additional evidence in favour of our model

Neutron and muon characterisation techniques for battery materials

Neutron and muon characterisation techniques offer unique capabilities for investigating the complex structure and dynamics of rechargeable battery systems. Whilst the non-monotonic interaction of the neutron with the nuclei of atoms makes it sensitive to light and neighbouring elements in the periodic table, its weakly interacting nature allows it to penetrate deep into the sample without damaging it, enabling the flexible use of complex sample environments such as in situ/in operando cells. Meanwhile, the also non-invasive nature of an implanted positive muon allows it to be used as a probe to study bulk ionic diffusion phenomena within materials at different depths by tuning the energy of the incident muons. This review discusses the application of relevant neutron and muon characterisation techniques to the study of specific phenomena in ion batteries, highlighting key literature cases that serve as the archetypal example for the utility of each technique. Furthermore, this review includes an accessible overview of the working principles of each technique that has been condensed and optimised to provide a basic understanding of their relevance to the particular challenges they can address

Future and potential spending on health 2015-40: Development assistance for health, and government, prepaid private, and out-of-pocket health spending in 184 countries

Background: The amount of resources, particularly prepaid resources, available for health can affect access to health care and health outcomes. Although health spending tends to increase with economic development, tremendous variation exists among health financing systems. Estimates of future spending can be beneficial for policy makers and planners, and can identify financing gaps. In this study, we estimate future gross domestic product (GDP), all-sector government spending, and health spending disaggregated by source, and we compare expected future spending to potential future spending. Methods: We extracted GDP, government spending in 184 countries from 1980-2015, and health spend data from 1995-2014. We used a series of ensemble models to estimate future GDP, all-sector government spending, development assistance for health, and government, out-of-pocket, and prepaid private health spending through 2040. We used frontier analyses to identify patterns exhibited by the countries that dedicate the most funding to health, and used these frontiers to estimate potential health spending for each low-income or middle-income country. All estimates are inflation and purchasing power adjusted. Findings: We estimated that global spending on health will increase from US$9.21 trillion in 2014 to$24.24 trillion (uncertainty interval [UI] 20.47-29.72) in 2040. We expect per capita health spending to increase fastest in upper-middle-income countries, at 5.3% (UI 4.1-6.8) per year. This growth is driven by continued growth in GDP, government spending, and government health spending. Lower-middle income countries are expected to grow at 4.2% (3.8-4.9). High-income countries are expected to grow at 2.1% (UI 1.8-2.4) and low-income countries are expected to grow at 1.8% (1.0-2.8). Despite this growth, health spending per capita in low-income countries is expected to remain low, at $154 (UI 133-181) per capita in 2030 and$195 (157-258) per capita in 2040. Increases in national health spending to reach the level of the countries who spend the most on health, relative to their level of economic development, would mean $321 (157-258) per capita was available for health in 2040 in low-income countries. Interpretation: Health spending is associated with economic development but past trends and relationships suggest that spending will remain variable, and low in some low-resource settings. Policy change could lead to increased health spending, although for the poorest countries external support might remain essential

Search for heavy resonances decaying into a Z or W boson and a Higgs boson in final states with leptons and b-jets in 139 fb−1 of pp collisions at s√ = 13 TeV with the ATLAS detector

This article presents a search for new resonances decaying into a Z or W boson and a 125 GeV Higgs boson h, and it targets the νν¯¯¯bb¯¯, ℓ+ℓ−bb¯¯, or ℓ±νbb¯¯ final states, where ℓ = e or μ, in proton-proton collisions at s√ = 13 TeV. The data used correspond to a total integrated luminosity of 139 fb−1 collected by the ATLAS detector during Run 2 of the LHC at CERN. The search is conducted by examining the reconstructed invariant or transverse mass distributions of Zh or Wh candidates for evidence of a localised excess in the mass range from 220 GeV to 5 TeV. No significant excess is observed and 95% confidence-level upper limits between 1.3 pb and 0.3 fb are placed on the production cross section times branching fraction of neutral and charged spin-1 resonances and CP-odd scalar bosons. These limits are converted into constraints on the parameter space of the Heavy Vector Triplet model and the two-Higgs-doublet model