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Linkages between dietary diversity and indicators of agricultural biodiversity in Burkina Faso
No full textThis paper assesses the relationships between women's dietary diversity and various indicators of agricultural biodiversity in farms of the Hauts-Bassins, a cotton-growing region in rural western Burkina Faso. A sample of 579 farms representative of the region was surveyed at three different periods of the year. Using a qualitative 24-h dietary recall, we computed a women's dietary diversity score (WDDS-10) based on ten food groups. We used four crop diversity indicators: crop count (CC), Simpson's index (SI), nutritional functional diversity (NFD) and production diversity score (PDS) based on the same food groups as in the WDDS-10. We also counted the number of agroforestry tree species that provide food and the number of animal species raised. Mean WDDS-10 was low (3.4 +/- 1.5 food groups) and did not vary between seasons, whereas the food groups consumed changed according to harvests. Farm production is based on cereals and cotton with low diversity (on average 2.2 +/- 1.0 food groups were cultivated on each farm). Results of mixed models showed that WDDS-10 is positively associated with PDS and the number of agroforestry trees species. In this area, dietary diversity of women in farming households depends on the on-farm production of nutritionally diverse crops, partly because when a crop is produced some of it is usually consumed by the members of the farm household. In addition, WDDS-10 was found to be negatively associated with cotton production when managed by male farm heads, but positively when managed by women. Our results show that assessing the relationships between WDDS-10 and agricultural biodiversity depends on how the latter is assessed. In Burkina Faso, enhancing agricultural biodiversity, especially nutrient-dense crops and agroforestry trees, could be an appropriate way to improve dietary diversity
Projection of upwelling-favorable winds in the Peruvian upwelling system under the RCP8.5 scenario using a high-resolution regional model
No full textThe Peruvian upwelling system (PUS) is the most productive Eastern Boundary Upwelling System (EBUS) of the world ocean. Contrarily to higher latitude EBUSs, there is no consensus yet on the response of upwelling-favorable winds to regional climate change in this region. Global climate models are not able to reproduce the nearshore surface winds, and only a few downscaling studies have been performed by using relatively coarse-grid atmospheric models forced by idealized climate change scenarios. In the present study, the impact of climate change on the PUS upwelling-favorable winds was assessed using a high resolution regional atmospheric model to dynamically downscale the multi-model mean projection of an ensemble of 31 CMIP5 global models under the RCP8.5 worst-case climate scenario. We performed a 10-year retrospective simulation (1994-2003) forced by NCEP2 reanalysis data and a 10-year climate change simulation forced by a climate change forcing (i.e. differences between monthly-mean climatologies for 2080-2100 and 1989-2009) from CMIP5 ensemble added to NCEP2 data. We found that changes in the mean upwelling-favorable winds are weak (less than 0.2 m s(-1)). Seasonally, summer winds weakly decrease (by 0-5%) whereas winter winds weakly increase (by 0-10%), thus slightly reinforcing the seasonal cycle. A momentum balance shows that the wind changes are mainly driven by the alongshore pressure gradient, except in a local area north of the Paracas peninsula, downstream the main upwelling center, where wind increase in winter is driven by the shoreward advection of offshore momentum. Sensitivity experiments show that the north-south sea surface temperature gradient plays an important role in the wind response along the north and central coasts, superimposed onto the South Pacific Anticyclone large-scale forcing. A reduction (increase) of the gradient induces a wind weakening (strengthening) up to 15% (25%) off the northern coast during summer. This local mechanism is not well represented in global climate models projections, which underlines the strong need for dynamical downscaling of coastal wind in order to study the impact of climate change on the Peruvian upwelling ecosystem
Variation in chemical composition and antimalarial activities of two samples of Terminalia albida collected from separate sites in Guinea
No full textBackground The disparity of harvesting locations can influence the chemical composition of a plant species, which could affect its quality and bioactivity. Terminalia albida is widely used in traditional Guinean medicine whose activity against malaria has been validated in vitro and in murine models. The present work investigated the antimalarial properties and chemical composition of two samples of T. albida collected from different locations in Guinea. Method T. albida samples were collected in different locations in Guinea, in Dubreka prefecture (West maritime Guinea) and in Kankan prefecture (eastern Guinea). The identity of the samples was confirmed by molecular analysis. In vitro antiplasmodial activity of the two extracts was determined against the chloroquine resistant strain PfK1. In vivo, extracts (100 mg/kg) were tested in two experimental murine models, respectively infected with P. chabaudi chabaudi and P. berghei ANKA. The chemical composition of the two samples was assessed by ultra-high-performance liquid chromatography coupled to high resolution mass spectrometry. Results In vitro, the Dubreka sample (TaD) was more active with an IC50 of 1.5 mu g/mL versus 8.5 mu g/mL for the extract from Kankan (TaK). In vivo, the antiparasitic effect of TaD was substantial with 56% of parasite inhibition at Day 10 post-infection in P. chabaudi infection and 61% at Day 8 in P. berghei model, compared to 14 and 19% inhibition respectively for the treatment with TaK. In addition, treatment with TaD further improved the survival of P. berghei infected-mice by 50% at Day 20, while the mortality rate of mice treated with Tak was similar to the untreated group. The LC/MS analysis of the two extracts identified 38 compounds, 15 of which were common to both samples while 9 and 14 other compounds were unique to TaD and TaK respectively. Conclusion This study highlights the variability in the chemical composition of the species T. albida when collected in different geographical locations. These chemical disparities were associated with variable antimalarial effects. From a public health perspective, these results underline the importance of defining chemical fingerprints related to botanical species identification and to biological activity, for the plants most commonly used in traditional medicine
Natural infection of free-ranging mandrills (Mandrillus sphinx) by enteroviruses and astroviruses in southern Gabon
No full textEnteroviruses (Picornaviridae) and astroviruses (Astroviridae) cause various diseases in humans and animals, including in non-human primates (NHPs). Some enteroviruses and astroviruses detected in NHPs are genetically related to those infecting humans, indicating the occurrence of interspecies transmissions. In this study, we screened 200 fecal samples of 56 free-ranging mandrills (Mandrillus sphinx) by nested reverse transcription-PCR with primers targeting the VPI and RdRp genes, to evaluate the diversity of enterovirus and astrovirus infection, respectively, and the associated zoonotic risk. Overall, ten samples from six mandrills were enterovirus-positive (5%), and three samples from three mandrills were astrovirus-positive (1.5%). This is the first evidence of astrovirus infection in mandrills. Phylogenetic analyses based on the VPI sequences revealed that all ten enterovirus sequences were part of the species Enterovirus J, suggesting low zoonotic risk. Phylogenetic analysis of the three astrovirus sequences showed that they all belonged to the Mamastrovirus genus. Two astrovirus sequences were highly divergent from all human astrovirus sequences (63.4-73% nucleotide identity), while one sequence (AstV-5) suggested cross-species transmission from humans to mandrills. Additional studies are needed to better characterize the identified astroviruses and to confirm whether mandrills are host of astroviruses than can be transmitted to humans
Examining systemic racism in "empowerment-based" HIV prevention research : reflections of a US-France research partnership
No full textFactors affecting adult body condition in the endangered northern rockhopper penguin
No full textUnderstanding the factors that drive the dynamics of populations of long-lived species presents a unique challenge for conservation management. Here, we investigated long-term change in the body condition of adult northern rockhopper penguins Eudyptes moseleyi at Amsterdam Island, southern Indian Ocean, which hosts 5-10% of the global population of this endangered species. Analysis of a long-term dataset (1994-2016), concurrent to the population's rapid decline, revealed no trend in adult northern rockhopper penguin body condition over time at the stages considered in this study, i.e. breeding and moulting. However, body condition varied between years and sexes and part of this variation was explained by environmental factors. Males were on average in better condition than females whatever the stage and individuals on average were in better condition during the moulting compared to the breeding period. The environmental conditions [sea surface temperature anomaly (SSTa), Subtropical Indian Ocean Dipole (SIOD) and Southern Annular Mode (SAM)] appeared to impact non-linearly the body condition. Overall, females were in better condition for negative values of SAM, SIOD and SSTa. The body condition of males exhibited similar but less complex and more significant patterns, with decreasing body condition for increasing SAM, SIOD and SSTa. The absence of long-term trends in male and female body condition suggests that the very low reproductive output and declining population since 1997 is probably not the result of environmental conditions during pre-breeding and pre-moult and necessitates further research into possible drivers during the breeding season
Salt layer characteristics in the Ghor Al-Haditha area, Jordan : comprehensive combined reprocessing of geophysical data
No full textThe presence of buried salt layer in the Ghor Al-Haditha area is discussed concerning sinkhole hazard. Numerous geophysical methods such as seismic refraction (SRFR), reflection (SRFL), seismic tomography, multichannel analysis of surface waves (MASW) were developed earlier for the salt layer identification. Geophysical criteria of salt parameters (such as longitudinal V-p and shear V-s wave velocities) were established to identify salt layers. This paper presents new geophysical results proving the salt extension in the Dead Sea (DS) coastal area in its eastern shore potentially representing a sinkhole hazard. The reprocessing technique of MASW data using the synthetic modeling enabled us to detect salt layer characteristics such as depth to its top, the thickness of the layer, and its V-s velocity. It was established that a salt layer with 7-10 m thick is located at a depth of 37-41 m and is characterized by shear-wave velocity (V-s) of 850-1200 m/s. Similar results were obtained by the Transient Electromagnetic (TEM) resistivity method, which detected a comparatively resistive salt layer at a background of very low resistivity. The resolution of the TEM method allows detecting a salt layer of 3 m thick and more at a depth of 39-40 m. Seismic refraction data processing has shown the presence of a salt layer with a velocity of more than 2900 m/s at approximately or the same depths. Analysis of seismic tomography data also confirms the parameters of the discovered target. Analysis of results of geophysical studies in the western and eastern DS shores, comparison of geological conditions in shores, and sinkhole development, enabled us to conclude with a high probability that salt layers exist in both shores and sinkhole development is determined here by similar mechanisms
Global climate pattern impacts on long-term olive yields in Northwestern Africa: case from Souss-Massa region
No full textIn arid to semi-arid regions, vulnerability to climate change combined with the overexploitation of water resources is jeopardizing food security. In the Souss-Massa region in central Morocco, the rural population relies on growing olives for a living. The management of these orchards is mostly traditional under rainfed irrigation, which induces a high level of dependence on climate variability. In the present study, we investigate the long-term trends of the relationship between the observed olive yields and global climate patterns during the period 1973-2014. We apply lagged Spearman's correlations and cross-wavelet analysis to detect the potential influence of El Nino-southern oscillation (ENSO), the Indian Ocean Dipole (IOD), North Atlantic oscillation (NAO) and Pacific decadal oscillation (PDO) on the yield variability of olive orchards. The results of a Mann-Kendall test show a statistically significant decreasing trend in olive yields during the studied period. Statistically significant negative correlations were observed for (lag = -1) with spring and summer NINO 3.4 and with summer and autumn PDO. No statistically significant correlations between olive yields and NAO and IOD were observed. The results of wavelet coherence between annual olive yields and PDO and ENSO revealed that the highest values of power spectrum coherence occurred during the (lag = 0) spring PDO and (lag = -1) spring ENSO, both with an antiphase relationship. During the studied period, the extreme events of El Nina and El Nino years corresponded to below average yields
Can organic amendments improve soil physical characteristics and increase maize performances in contrasting soil water regimes ?
No full textOrganic amendments are believed to help increase the soil carbon storage and therefore improve soil quality, which may be important in the context of climate change. However, the added value of organic amendments for farmers must be clearly demonstrated in order to convince them of the utility of their use. The aims of this study were: (i) to investigate the impact on maize of compost and vermicompost combined with two levels (negligible and significant) of plant water stress; and (ii) to determine how the organic amendments affected the soil's physical properties and maize productivity. Water stress levels were imposed by controlling the matric potential of soil columns in which cultivated soil characteristics was mimicked (10 cm topsoil with organic amendments, above a 50 cm subsoil without any inputs containing the majority of the roots). Plant and soil characteristics were monitored daily for 70 days. Our results show that the use of organic amendments is profitable for farmers as: (i) maize performances were increased in both moisture regimes; and (ii) the improvement was particularly striking in terms of yield. No additional benefits were measured when using vermicompost instead of compost. The data suggest that the improvement in plant characteristics did not result from increased water storage in the soils with organic amendments, but rather from better access to the water, resulting in faster root development in the macroporosity of the amended soils
The digestive function of Pseudoplatystoma punctifer early juveniles is differentially modulated by dietary protein, lipid and carbohydrate content and their ratios
No full textSimple Summary The Neotropical catfish Pseudoplatystoma punctifer is a promising candidate species for aquaculture diversification in the Amazon basin. However, optimized feeding strategies are needed to improve growth and survival during the early life stages. In order to determine the nutritional needs of early juveniles, the influence of four diets containing different protein and lipid content in their digestive physiology and performance was evaluated. To do so, the gene expression and the activity of the main digestive enzymes, the histology of the digestive organs, and the incorporation of the dietary macronutrients in the body tissue of fish fed the different diets were analyzed. The diet containing the highest protein and lipid content promoted the fastest development of the digestive capacities, resulting in a better growth and survival that increased sixfold and twofold, respectively, in comparison to previous feeding protocols. Lipids were favored over carbohydrates as a source of energy and excessive carbohydrate content led to unbalanced lipid metabolism and fat deposition in the liver. This study provided new knowledge on the molecular and biochemical mechanisms underlying nutrient digestion in this species and on the nutritional needs of early juveniles, which represents a significant contribution towards the establishment of its commercial culture. Pseudoplatystoma punctifer is an Amazonian catfish highly appreciated for its high flesh quality, size, and commercial value. Its aquaculture is pursued to satisfy the demands of an increasing population in the region. However, knowledge of the nutritional needs during the early life stages is necessary for improving growth and reducing the incidence of cannibalism, factors that limit the success of its commercial farming. This study aimed at evaluating the influence of four diets containing different protein and lipid levels (30:15, 30:10, 45:15, or 45:10 in %) in the digestive physiology and performance of early juveniles. The results showed that the dietary protein:lipid as well as carbohydrate levels and ratios influenced differently the whole-body proximate composition, the digestive physiology and development, and hence growth and survival. The 45:15 diet promoted the best growth, survival, and the most rapid development of the digestive system, as shown at histological (higher number of hepatocytes, goblet cells in the anterior intestine and enterocytes in all intestinal portions, and longer folds in the posterior intestine), molecular (highest amylase, lipoprotein lipase, phospholipase, trypsinogen, and pepsinogen gene expression), and biochemical (highest lipase and pepsin activities and higher alkaline phosphatase:leucine alanine peptidase activity ratio) levels. Lipids were favored over carbohydrates as source of energy, with lipids promoting a protein-sparing effect at adequate energy:protein ratio. Carbohydrate content higher than 25% was excessive for this species, leading to unbalanced lipid metabolism and fat deposition in the liver