Distortions to Agricultural Incentives in Uganda

Distorted incentives, agricultural and trade policy reforms, national agricultural development, Agricultural and Food Policy, International Relations/Trade, F13, F14, Q17, Q18,

Monitoring vaccination coverage: Defining the role of surveys.

Vaccination coverage is a widely used indicator of programme performance, measured by registries, routine administrative reports or household surveys. Because the population denominator and the reported number of vaccinations used in administrative estimates are often inaccurate, survey data are often considered to be more reliable. Many countries obtain survey data on vaccination coverage every 3-5years from large-scale multi-purpose survey programs. Additional surveys may be needed to evaluate coverage in Supplemental Immunization Activities such as measles or polio campaigns, or after major changes have occurred in the vaccination programme or its context. When a coverage survey is undertaken, rigorous statistical principles and field protocols should be followed to avoid selection bias and information bias. This requires substantial time, expertise and resources hence the role of vaccination coverage surveys in programme monitoring needs to be carefully defined. At times, programmatic monitoring may be more appropriate and provides data to guide program improvement. Practical field methods such as health facility-based assessments can evaluate multiple aspects of service provision, costs, coverage (among clinic attendees) and data quality. Similarly, purposeful sampling or censuses of specific populations can help local health workers evaluate their own performance and understand community attitudes, without trying to claim that the results are representative of the entire population. Administrative reports enable programme managers to do real-time monitoring, investigate potential problems and take timely remedial action, thus improvement of administrative estimates is of high priority. Most importantly, investment in collecting data needs to be complemented by investment in acting on results to improve performance

LʼOccident grec de Marseille à Mégara Hyblaea

La recherche sur l’expansion grecque en Méditerranée occidentale à l’époque archaïque a largement progressé en France pendant les quarante dernières années grâce aux travaux d’Henri Tréziny et aux pistes qu’il a lancées dans l’interprétation des découvertes archéologiques de Sicile et du Sud de la Gaule. En présentant ces études sur l’urbanisme, l’architecture et divers artefacts de la vie matérielle dans ces régions occupées par les Grecs à partir du VIIIe siècle av. J.-C., ses amis, collègues et élèves ont voulu lui rendre hommage en centrant en particulier leurs réflexions sur les deux sites qui ont constitué les piliers de sa carrière, Marseille et Mégara Hyblaea. Vingt-trois contributions dues à quelques-uns des meilleurs spécialistes de ces questions, français, italiens et espagnols, mettent ici en évidence le dynamisme de la recherche dans ces régions périphériques du monde grec où populations locales et Grecs ont constitué une culture spécifique, faite de brassages et d’emprunts respectifs dans les domaines de la ville, de la religion ou des pratiques culturelles. Le volume s’ouvre sur la publication de découvertes récentes des chercheurs turcs à Phocée, la métropole de Marseille et une des cités grecques les plus actives dans cette expansion vers l’Ouest

Immunization programs and their costs

The Expanded Program on Immunization (EPI) has made considerable progress towards immunizing the world's women and children, preventing 3.2 million child death episodes per year from measles, neonatal tetanus, and pertusis, as well as 440,000 cases of paralytic poliomyelitis. Vaccinations provided through the EPI are believed to be one of the most cost-effective child survival interventions at a cost between $5 and$10 per child. However, variation exists in the average cost per fully immunized child, depending upon the type of vaccine technology and delivery strategy utilized, the scale of operation, and country and environmental characteristics. Recent evidence on the cost-effectiveness of immunization strategies raise concerns over the affordability of national immunization programs by governments and highlights the need for continued donor support, identification of other financing mechanisms, or reconsideration of policies aimed toward accelerating and maintaining immunization coverage.cost-effectiveness immunization sustainability developing countries

Cost-effectiveness and user characteristics of clinic based services for the treatment of diarrhea: A case study in Bangladesh

This study compares the cost-effectiveness of three services for the treatment of diarrhea, in a rural area of Bangladesh. It also examines patterns of user composition, and how these depend on factors other than disease severity and incidence. The three services are a large hospital-style treatment center, an ambulance system bringing patients from greater distances, and a small treatment center staffed by paramedics. The results show that the long run average cost per patient is about $16 at the large center, with an additional$13 if the patient came by ambulance, compared to $3 at the small center. Corresponding costs per death averted were$1300, an additional $360, and$190 respectively. Previous studies have suggested that there is no more cost-effective alternative for the prevention of diarrhea, although in future home-based oral rehydration therapy may be a potential alternative. Each service exhibits use patterns suggesting that males and especially small boys receive preferential access to treatment. This bias is exacerbated as distance from the center increases, or if a fee is charged. The study concludes firstly that diarrhea treatment costs in clinics are relatively high, and secondly that unintended biases in service use should be an important consideration in service design.

Effects of simulated benthic fluxes on phytoplankton dynamic and photosynthetic parameters in a mesocosm experiment (Bay of Brest, France)

International audienceBenthic faunal activity and density play an important role in determining the rates of benthic nutrient fluxes, which enrich the water column and contribute to phytoplankton growth. The intensity of nutrient fluxes in the Bay of Brest depends on the density of the invasive gastropod, Crepidula fornicata. In order to study the impact of benthic fluxes on phytoplankton dynamics, realistic daily nutrient inputs simulating various densities of C. fornicata were added to six enclosures during three weeks. The increase in fertilization intensity influenced the phytoplankton biomass. A succession from Chaetoceros spp. to Pseudo-nitzschia spp. and Leptocylindrus danicus was observed in all enclosures, but the dynamics of successions were different. Pseudo-nitzschia spp. was favored in the three more fertilized enclosures, while Chaetoceros spp. persisted longer in less enriched enclosures. Despite an apparent nitrogen limitation, the quantum efficiency of PSII (Fv/Fm) was high (>0.5) and stable in all enclosures. The maximal photosynthetic capacity (PBmax) was also invariable and oscillated around an average value of 2.23 mg C (mg Chl a)−1 h−1. The stability of Fv/Fm and PBmax observed at different nutrient input intensities demonstrates that the daily inputs maintained the physiological balance of the microalgae. The maximal light utilization efficiency (α) and the light saturation parameter (Ek) were also quite stable after day 8, which reveals that photosynthetic parameters were driven by growth constraints due to nutrient availability and not by incident light or species successions. We suggest that our results correspond to an "Ek independent variation" regulation. We propose that such regulation of photosynthetic parameters appears when there are frequent nutrient additions which do not allow replete nutrient conditions to be reached but lead to physiological equilibrium. Thanks to our results we can understand how even low benthic fluxes, by supporting their cellular physiological status, allowed diatoms to dominate the phytoplankton community in the six enclosures. These results confirm the importance of daily benthic inputs as much as the amount of nutrient inputs. However, we suggest that high benthic fluxes have a buffering effect on nutrient availability, thereby limiting the consequences of short-term events which can entail a sudden increase of nutrient input, and are known to promote Dinophyta bloom formation

Response of a phytoplankton community to increased nutrient inputs: A mesocosm experiment in the Bay of Brest (France)

International audienceIn the Bay of Brest (France), benthic fluxes of silicic acid (DSi) are thought to be strongly involved in diatom dominance and their intensity depends on the density of an invasive gastropod, Crepidula fornicata. While the proliferation of this gastropod is likely to support diatom dominance, local fishermen have proposed its removal as it perturbs the development of the native Great Scallop, Pecten maximus. However, such a removal may be associated with potentially harmful algal blooms. The response of the phytoplankton community to modifications of the benthic fluxes of DSi, resulting from a further proliferation or the removal of C fornicata, was examined in a mesocosm nutrient enrichment experiment over a period of 16 days in the spring of 2004. Six mesocosms (5.4 m(3)) were filled using a natural planktonic assemblage from the Bay and received N, P and Si additions at the stoichiometric ratio of the in situ benthic fluxes (Si:N:P=16:16:1), with a gradient of enrichment ranging from 0 to almost 4 times the maximal benthic flux measured in the Bay. The diatom Chaetoceros (mainly C. debilis) rapidly outgrew non-siliceous species of microphytoplankton in all enclosures although kinetic experiments provided direct evidence of Si limitation. This dominance of diatoms at DSi concentrations <2 mu M highlighted that the residual DSi concentration measured daily in the mesocosms is not a reliable criterion to predict diatom dominance in marine ecosystems whereas the dependence of the Si uptake rate on fertilization rates suggests that emphasis should be placed on daily nutrient addition. Quantitative modifications of nutrient additions only changed the magnitude of the diatom bloom and high fertilization rates may lead to high sedimentation fluxes of organic material, which can strongly harm the entire benthic community. Finally the diatom dominance at low fertilization rates raised questions about the role of benthic fluxes in preventing harmful algal blooms within the Bay system

Annual Phytoplankton Primary Production Estimation in a Temperate Estuary by Coupling PAM and Carbon Incorporation Methods

Phytoplankton primary production varies considerably with environmental parameters especially in dynamic ecosystems like estuaries. The aim of this study was to investigate short-term primary production along the salinity gradient of a temperate estuary over the course of 1 year. The combination of carbon incorporation and fluorescence methods enabled primary production estimation at short spatial and temporal scales. The electron requirement for carbon fixation was investigated in relation with physical-chemical parameters to accurately estimate primary production at high frequency. These results combined with the variability of the photic layer allowed the annual estimation of primary production along the estuary. Phytoplankton dynamics was closely related to salinity and turbidity gradients, which strongly influenced cells physiology and photoacclimatation. The number of electrons required to fix 1 mol of carbon (C) was ranged between 1.6 and 25 mol electron mol C−1 with a mean annual value of 8 ± 5 mol electron mol C−1. This optimum value suggests that in nutrient replete conditions like estuaries, alternative electron flows are low, while electrons transfer from photosystem II to carbon fixation is highly efficient. A statistical model was used to improve the estimation of primary production from electron transport rate as a function of significant environmental parameters. Based on this model, daily carbon production in the Seine estuary (France) was estimated by considering light and photic zone variability. A mean annual daily primary production of 0.12 ± 0.18 g C m−2 day−1 with a maximum of 1.18 g C m−2 day−1 in summer was estimated which lead to an annual mean of 64.75 g C m−2 year−1. This approach should be applied more frequently in dynamic ecosystems such as estuaries or coastal waters to accurately estimate primary production in those valuable ecosystems