An operational approach to high resolution agro-ecological zoning in West-Africa.
ABSTRACT: The objective of this work is to develop a simple methodology for high resolution crop suitability analysis under current and future climate, easily applicable and useful in Least Developed Countries. The approach addresses both regional planning in the context of climate change projections and pre-emptive short-term rural extension interventions based on same-year agricultural season forecasts, while implemented with off-the-shelf resources. The developed tools are applied operationally in a case-study developed in three regions of Guinea-Bissau and the obtained results, as well as the advantages and limitations of methods applied, are discussed. In this paper we show how a simple approach can easily generate information on climate vulnerability and how it can be operationally used in rural extension services.
Project description:The concept of ecosystem services (ES) supply and demand has attracted increasing attention in science and policy making because it effectively links ecosystem services to human well-being. The imbalance of ES supply and demand in urban areas has become a key issue in regional sustainable development. In this context, we calculated ES supply and demand for Wuhan City, China, using the ES supply and demand ratio (ESDR) and the comprehensive ES supply-demand ratio (CESDR) to express the relationship between ES supply and demand. Ecological zoning was proposed according to the spatial differentiation of the ES supply-demand relationship, and policy recommendations are made. The results show that from the perspective of total ES supply and demand, the water yield supply (SWY), grain yield supply (SGY), and recreation services supply (SRS) are greater than the water yield demand (DWY), grain yield demand (DGY), and recreation services demand (DRS), and that the climate regulation supply (SCR) is less than the climate regulation demand (DCR). From a spatial perspective, there are imbalances and mismatches in ES supply and demand, especially in urban central areas. The values of SWY, SGY, SCS, and SRS per unit area are less than their respective demand values, and the area of mismatch has expanded with the gradual increase of the built-up area. The spatial pattern of ES supply and demand is circular, with the form of "deficit zone-relative equilibrium zone-surplus zone", which corresponds to "urban central area-near suburbs-distant suburbs and rural areas".
Project description:Crop yields are affected by unfavourable/extreme weather and climate events occurring during sensitive growth stages. Understanding the risks associated with these events is essential to adapt agro-management decisions and reduce losses. For this purpose, we propose a targeted climate service integrating a dynamic crop phenology model with an approach based on dedicated agro-climate risk indicators. The initial set of these indicators has been developed in a co-design approach with agronomists and durum wheat farmers participating as end-users in the H2020-MedGOLD project. Four groups of indicators characterize drought events, excessive wetness, cold stress and heat stress during sensitive growth stages. The proposed approach has been fully implemented as an R-package named <i>Clisagri</i>. The package is complemented with a set of optimization functions, which target optimal variety selection in terms of crop cycle duration.
Project description:The HIV-1 epidemic in West Africa has been dominated by subtype A and the recombinant form CRF02_AG. Little is known about the origins and the evolutionary history of HIV-1 in this region. We employed Maximum likelihood and Bayesian methods in combination with temporal and spatial information to reconstruct the HIV-1 subtype distribution, demographic history and migration patterns over time in Guinea-Bissau, West Africa. We found that CRF02_AG and subsubtype A3 were the dominant forms of HIV-1 in Guinea-Bissau and that they were introduced into the country on at least six different occasions between 1976 and 1981. These estimates also corresponded well with the first reported HIV-1 cases in Guinea-Bissau. Migration analyses suggested that (1) the HIV-1 epidemic started in the capital Bissau and then dispersed into more rural areas, and (2) the epidemic in Guinea-Bissau was connected to both Cameroon and Mali. This is the first study that describes the HIV-1 molecular epidemiology in a West African country by combining the results of subtype distribution with analyses of epidemic origin and epidemiological linkage between locations. The multiple introductions of HIV-1 into Guinea-Bissau, during a short time-period of five years, coincided with and were likely influenced by the major immigration wave into the country that followed the end of the independence war (1963-1974).
Project description:The World Health Organization (WHO) classifies Guinea-Bissau as having severe vitamin A deficiency (VAD). To date, no national survey has been conducted. We assessed vitamin A status among children in rural Guinea-Bissau to assess status and identify risk factors for VAD.In a vitamin A supplementation trial in rural Guinea-Bissau, children aged 6 months to 2 years who were missing one or more vaccines were enrolled, vaccinated and randomized to vitamin A or placebo. Provided consent, a dried blood spot (DBS) sample was obtained from a subgroup of participants prior to supplementation. Vitamin A status and current infection was assessed by an ELISA measuring retinol-binding protein (RBP) and C-reactive protein (CRP). VAD was defined as RBP concentrations equivalent to plasma retinol <0.7 ?mol/L; infection was defined as CRP >5 ml/L. In Poisson regression models providing prevalence ratios (PR), we investigated putative risk factors for VAD including sex, age, child factors, maternal factors, season (rainy: June-November; dry: December-May), geography, and use of health services.Based on DBS from 1102 children, the VAD prevalence was 65.7% (95% confidence interval 62.9-68.5), 11% higher than the WHO estimate of 54.7% (9.9-93.0). If children with infection were excluded, the prevalence was 60.2% (56.7-63.7). In the age group 9-11 months, there was no difference in prevalence of VAD among children who had received previous vaccines in a timely fashion and those who had not. Controlled for infection and other determinants of VAD, the prevalence of VAD was 1.64 (1.49-1.81) times higher in the rainy season compared to the dry, and varied up to 2-fold between ethnic groups and regions. Compared with having an inactivated vaccine as the most recent vaccine, having a live vaccine as the most recent vaccination was associated with lower prevalence of VAD (PR=0.84 (0.74-0.96)).The prevalence of VAD was high in rural Guinea-Bissau. VAD varied significantly with season, ethnicity, region, and vaccination status.Clinicaltrials.gov NCT00514891.
Project description:A two-step method has been developed to synthesize several biologically important iminocyclitols in ca. 44-60% yields by using Petasis-type condensation. The method is very general and operationally simple, affording a series of iminocyclitols from easily available sugar derivatives. Unexpected diastereoselectivities are observed, suggesting that the condensation may proceed through a five- or six-membered cyclic iminium ion intermediate.
Project description:Climate is one of the most important factors in agricultural productivity, which could directly or indirectly influence productivity since the climate is linked to physiological processes. It is, therefore, essential to understanding the various strategies used by farmers to mitigate the adverse impact of climate change and the factors that influence maize farmers' adoption and intensity of climate change adaptation strategies among smallholder maize farmers in South-west Nigeria. In all, a sample of three hundred and thirty (311) smallholder maize farmers were interviewed. A double-hurdle count data model was employed to estimate the factors influencing farmers' adoption of adaptation strategies while accounting for selection bias with the plugging of inverse mill ratio (IMR) as a regressor. Significant variables such as household size, depreciation ratio, frequency of extension visits, access to extension, and non-farm income were factors influencing the adoption of climate change adaptation strategies among maize farmers. Age of the respondent, age square, household size, farm-based organization (FBO), non-farm income, climate information, access to credit, farmers residing in Osun State (location_Osun), distance to market significantly influenced the intensity of climate change adaptation strategies. This study, therefore, concluded that farm-level policy efforts that aim to improve rural development should focus on farmers' membership in FBO, increase the visits of extension agents, encourage non-farm income and access to climate change information, particularly during the off-cropping season. Policies and investment strategies of the government should be geared towards supporting improved extension service, providing on-farm demonstration training, and disseminating information about climate change adaptation strategies, particularly for smallholder farmers in Nigeria.
Project description:Misinformation can undermine a well-functioning democracy. For example, public misconceptions about climate change can lead to lowered acceptance of the reality of climate change and lowered support for mitigation policies. This study experimentally explored the impact of misinformation about climate change and tested several pre-emptive interventions designed to reduce the influence of misinformation. We found that false-balance media coverage (giving contrarian views equal voice with climate scientists) lowered perceived consensus overall, although the effect was greater among free-market supporters. Likewise, misinformation that confuses people about the level of scientific agreement regarding anthropogenic global warming (AGW) had a polarizing effect, with free-market supporters reducing their acceptance of AGW and those with low free-market support increasing their acceptance of AGW. However, we found that inoculating messages that (1) explain the flawed argumentation technique used in the misinformation or that (2) highlight the scientific consensus on climate change were effective in neutralizing those adverse effects of misinformation. We recommend that climate communication messages should take into account ways in which scientific content can be distorted, and include pre-emptive inoculation messages.
Project description:A convenient CuI/L-proline-catalyzed, two-step one-pot method has been developed for the preparation of indolo[1,2-a]quinazoline derivatives using a sequential Ullmann-type C-C and C-N coupling. This protocol provides an operationally simple and rapid strategy for preparing indolo[1,2-a]quinazoline derivatives and displays good functional group tolerance. All the starting materials are commercial available or can be easily prepared.
Project description:INTRODUCTION:Though still high, the infant mortality rate in Guinea-Bissau has declined. We aimed to identify risk factors including vaccination coverage, for infant mortality in the rural population of Guinea-Bissau and assess whether these risk factors changed from 1992-3 to 2002-3. METHODS:The Bandim Health Project (BHP) continuously surveys children in rural Guinea-Bissau. We investigated the association between maternal and infant factors (especially DTP and measles coverage) and infant mortality. Hazard ratios (HR) were calculated using Cox regression. We tested for interactions with sex, age groups (defined by current vaccination schedule) and cohort to assess whether the risk factors were the same for boys and girls, in different age groups in 1992-3 and in 2002-3. RESULTS:The infant mortality rate declined from 148/1000 person years (PYRS) in 1992-3 to 124/1000 PYRS in 2002-3 (HR = 0.88;95%CI:0.77-0.99); this decline was significant for girls (0.77;0.64-0.94) but not for boys (0.97;0.82-1.15) (p = 0.10 for interaction). Risk factors did not differ significantly by cohort in either distribution or effect. Mortality decline was most marked among girls aged 9-11 months (0.56;0.37-0.83). There was no significant mortality decline for girls 1.5-8 months of age (0.93;0.68-1.28) (p = 0.05 for interaction). DTP and measles coverage increased from 1992-3 to 2002-3. CONCLUSIONS:Risk factors did not change with the decline in mortality. Due to beneficial non-specific effects for girls, the increased coverage of measles vaccination may have contributed to the disproportional decline in mortality by sex and age group.
Project description:<h4>Background</h4>Participatory health education interventions and/or community-based primary health care in remote regions can improve child survival. The most recent data from Guinea Bissau shows that the country ranks 5th from bottom globally with an under-five mortality rate of 198 per 1000 live births in 2007. EPICS (Enabling Parents to Increase Child Survival) is a cluster randomised trial, which is currently running in rural areas of southern Guinea Bissau. It aims to evaluate whether an intervention package can generate a rapid and cost-effective reduction in under-five child mortality. The purpose of the study described here was to understand levels of knowledge on child health and treatment-seeking and preventative behaviours in southern Guinea Bissau in order to develop an effective health education component for the EPICS trial. The study also aimed to assess the effect of gender and ethnicity on knowledge and behaviour.<h4>Methods</h4>Women and men were interviewed in their households using a structured questionnaire. Characteristics of the households and of the interviewed women and men were tabulated. The number of correct answers given to the health knowledge and practice questions and their percentage distribution were tabulated by items and by gender. An overall health knowledge score was derived.<h4>Results</h4>There are low levels of appropriate knowledge on child health, some inappropriate practices and generally low vaccination coverage. Health knowledge scores improve significantly amongst those who have accessed higher education. Differences in health knowledge between women and men become insignificant once age and education are accounted for.<h4>Conclusions</h4>Health education activities should be an integral part of a package to improve child survival in rural Guinea Bissau. These activities should focus on diarrhoea, malaria, pneumonia, pregnancy, delivery, neonatal care and vaccination coverage, as these are areas where knowledge and practices were found to be inadequate in this study. Men as well as women should be involved in these activities. Prior to developing health education interventions in similar settings, studies to assess areas to be targeted should be conducted.