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Enseigner l&8217;histoire à l&8217;heure de l&8217;ébranlement colonial. Soudan, Égypte et empire britannique (1943&8211;1960) by Iris Seri-Hersch. - Paris : IISMM/Karthala, 2018 [Book review]
No full textBeyond flowers : including non-floral resources in bee conservation schemes
No full textLand-use change and habitat loss have profoundly disturbed the resource availability for many organisms in farmlands, including bees. To counteract the resulting decline of bees and to maintain their pollination service to crops, bee pollinator-friendly schemes have been developed. We assessed the most established bee pollinator-friendly schemes which mainly aim at enhancing the availability of floral food resources and, or, nesting sites. We found that the availability of non-floral resources was typically overlooked in these schemes, although more than 30% of bee species worldwide depend on non-floral resources. In this opinion paper, we call for more attention on the role of non-floral resources in such conservation schemes. In fact, at least two of the most species rich Apoidea families, the Apidae and Megachilidae, need non-floral resources for nest building, defence, protection and health. For example, resin is known to improve health and resistance to pests and pathogens in stingless bees and the western honey bee Apis mellifera. Beyond social bees, many solitary bee species, in particularly within the Euglossini, Centridini and Megachilidae, also use resin, leaf pieces, trichome secretions and other materials for the construction and protection of brood cells and the nest. Besides protection, non-floral resources can also provide alternative food resources for bees, e.g. sugary secretions from other insects. Surprisingly little is known on this insect-insect interaction although some studies suggest that honey production by beekeepers can largely depend on this alternative food resource. The apparent knowledge gap on the role of non-floral resources for bees can thus directly concern stakeholders. Interestingly, many non-floral resources are provided by woody vegetation, but most of the bee pollinator-friendly schemes are currently orientated towards enhancing flower availability in field margins and flower strips. We therefore suggest more attention in the protection of trees and hedgerows in conservation, restoration and management schemes to best supporting bee health by providing combined access to nesting, floral and non-floral foraging resources
Downstream erosion and deposition dynamics of fine suspended sediments due to dam flushing
No full textFine sediment dynamics downstream dams is a key issue when dealing with environmental impact of hydraulic flushing. This paper presents an analysis of six field campaigns carried out during dam flushing events (in June 2006, 2007, 2009, 2010, 2011, and 2012) in the Arc- Isere river system in the Northern French Alps. Suspended sediment concentrations (SSC) and discharges were evaluated using direct measurements or/and 1D hydraulic modelling at up to 14 locations along the 120 kilometres-long river channel. The total suspended sediment flux (SSF) is analysed along the Arc and Isere rivers for each Arc dam flushing event. Uncertainties were quantified based on a propagation method of both measurement and modelling errors. The resulting confidence interval provides elements of discussion on the significance of the sediment mass balance between two consecutive measurement sites. Whereas the discharge time-series of each flushing event is roughly the same, the quantity of fine sediments removed from the reservoirs varied from 10,000 tons in 2007 to 40,000 tons in 2006. Also, a significant erosion is observed in the river system for some events (20,000 tons in 2007) while the SSF barely varied for other events (in 2009 and 2011). This detailed data set allows to identify specific locations in the river network where deposition or erosion occurred. This dynamics is closely related to both the hydrology in the upper Isere River and the morphology of the Arc and Isere rivers, which have been affected by the 2008 and 2010 floods
Thermal activation of persulfates for wastewater depollution on pilot scale solar equipment
No full textThermal activation of new oxidant chemicals like Persulfate (PS) has recently gained attention in driving advanced oxidation processes (AOP) for a number of applications. On the other hand, addressing energy demand with carbon free and sustainable energy solutions represents an asset for new technologies in the modern society. This paper then investigates on the removal of pharmaceuticals residues in wastewater (WW), conducted with PS advanced oxidation reactions on a solar thermal pilot equipment. Indoor preliminary investigations on small scale laboratory experimentations show how increasing temperature has a direct positive impact on pollutants degradations rate (k(app) value ranging from 0.4.10(-3) s(-1) at ambient to 10.4.10(-3) s at 75 degrees C). However, after an experimental screening methodology, 65 degrees C and 200 mu M appear as the appropriate target temperature and PS oxidant dosage to cope with both activation of PS oxidant and degradation of ten target micropollutants typically found in WW stream. Outdoor experimentations on the solar pilot equipment were conducted according to a batch running mode at a treatment capacity scale of a cubic meter. 95% pollutant removal rate is achieved within 2 h once the temperature has raised up to the target value (65 degrees C) in the bulk treated WW effluent. Series of treatment cycles under the natural day/night period demonstrate the reproducibility of the performance. As an early step result of the process optimization approach, heat recovery demonstration on the pilot equipment improves significantly the energetic balance over the now innovative thermal solar water treatment
Fault zones in limestones : impact on karstogenesis and groundwater flow (Lez aquifer, southern France)
No full textThe Lez aquifer in southern France comprises low-porosity karstified limestones and provides drinking water for similar to 400,000 inhabitants. Population growth and climate change have increased the stress on the water resources. In order to provide long-term protection and to optimize the water supply, the hydrogeology of the Lez aquifer must be better characterized. This study focused particularly on the St-Clement major fault zone (12 km long with a 500-m normal throw) which was structurally characterized using accurate geological mapping of the area, outcrops analysis and geophysics tools. The research highlights and explains the close relationship between the fault and the karstic occurrences. Moreover, tracer tests and piezometric head variations in boreholes have shown (1) strong interconnection between the observed karstic formations and (2) the major role of St-Clement fault on mass and pressure transfers in the aquifer. At the reservoir scale, the other major faults of the Lez aquifer, such as Corconne-Matelles or Gourg Noir faults, have shown some common morphologic and dynamic characteristics, and suggest a similar hydrogeological functioning. This study then extends this model to a larger scale. It proposes that, in aquifers of low-porosity carbonates, fault zones control the development of the main karstic network which, in turn, controls the main groundwater flows. Thus, faults should be reconsidered in order to improve the vulnerability studies and the quality of karstic aquifer modelling. Therefore, this report can contribute to protecting the groundwater resource, improving yields and optimizing groundwater supply exploitation in this type of aquifer
Implementing performance-based financing in peripheral health centres in Mali : what can we learn from it ?
No full textIntroductionNumerous sub-Saharan African countries have experimented with performance-based financing (PBF) with the goal of improving health system performance. To date, few articles have examined the implementation of this type of complex intervention in Francophone West Africa. This qualitative research aims to understand the process of implementing a PBF pilot project in Mali's Koulikoro region.MethodWe conducted a contrasted multiple case study of performance in 12 community health centres in three districts. We collected 161 semi-structured interviews, 69 informal interviews and 96 non-participant observation sessions. Data collection and analysis were guided by the Consolidated Framework for Implementation Research adapted to the research topic and local context.ResultsOur analysis revealed that the internal context of the PBF implementation played a key role in the process. High-performing centres exercised leadership and commitment more strongly than low-performing ones. These two characteristics were associated with taking initiatives to promote PBF implementation and strengthening team spirit. Information regarding the intervention was best appropriated by qualified health professionals. However, the limited duration of the implementation did not allow for the emergence of networks or champions. The enthusiasm initially generated by PBF quickly dissipated, mainly due to delays in the implementation schedule and the payment modalities.ConclusionPBF is a complex intervention in which many actors intervene in diverse contexts. The initial level of performance and the internal and external contexts of primary healthcare facilities influence the implementation of PBF. Future work in this area would benefit from an interdisciplinary approach combining public health and anthropology to better understand such an intervention. The deductive-inductive approach must be the stepping-stone of such a methodological approach
Region-wide annual glacier surface mass balance for the European Alps from 2000 to 2016
No full textStudying glacier mass changes at regional scale provides critical insights into the impact of climate change on glacierized regions, but is impractical usingin situestimates alone due to logistical and human constraints. We present annual mass-balance time series for 239 glaciers in the European Alps, using optical satellite images for the period of 2000 to 2016. Our approach, called the SLA-method, is based on the estimation of the glacier snowline altitude (SLA) for each year combined with the geodetic mass balance over the study period to derive the annual mass balance.In situannual mass-balances from 23 glaciers were used to validate our approach and underline its robustness to generate annual mass-balance time series. Such temporally-resolved observations provide a unique potential to investigate the behavior of glaciers in regions where few or no data are available. At the European Alps scale, our geodetic estimate was performed for 361 glaciers (75% of the glacierized area) and indicates a mean annual mass loss of -0.74 +/- 0.20 m w.e. yr(-1)from 2000 to 2016. The spatial variability in the average glacier mass loss is significantly correlated to three morpho-topographic variables (mean glacier slope, median, and maximum altitudes), altogether explaining 36% of the observed variance. Comparing the mass losses fromin situand SLA-method estimates and taking into account the glacier slope and maximum elevation, we show that steeper glaciers and glaciers with higher maximum elevation experienced less mass loss. Because steeper glaciers (>20 degrees) are poorly represented byin situestimates, we suggest that region-wide extrapolation of field measurements could be improved by including a morpho-topographic dependency. The analysis of the annual mass changes with regard to a global atmospheric dataset (ERA5) showed that: (i) extreme climate events are registered by all glaciers across the European Alps, and we identified opposite weather regimes favorable or detrimental to the mass change; (ii) the interannual variability of glacier mass balances in the "central European Alps" is lower; and (iii) current strong imbalance of glaciers in the European Alps is likely mainly the consequence of the multi-decadal increasing trend in atmospheric temperature, clearly documented from ERA5 data
Survey on non-human primates and mosquitoes does not provide evidences of spillover/spillback between the urban and sylvatic cycles of yellow fever and zika viruses following severe outbreaks in southeast Brazil
No full textIn the last decade, Flaviviruses such as yellow fever (YFV) and Zika (ZIKV) have expanded their transmission areas. These viruses originated in Africa, where they exhibit both sylvatic and interhuman transmission cycles. In Brazil, the risk of YFV urbanization has grown, with the sylvatic transmission approaching the most densely populated metropolis, while concern about ZIKV spillback to a sylvatic cycle has risen. To investigate these health threats, we carried out extensive collections and arbovirus screening of 144 free-living, non-human primates (NHPs) and 5219 mosquitoes before, during, and after ZIKV and YFV outbreaks (2015-2018) in southeast Brazil. ZIKV infection was not detected in any NHP collected at any time. In contrast, current and previous YFV infections were detected in NHPs sampled between 2017 and 2018, but not before the onset of the YFV outbreak. Mosquito pools screened by high-throughput PCR were positive for YFV when captured in the wild and during the YFV outbreak, but were negative for 94 other arboviruses, including ZIKV, regardless of the time of collection. In conclusion, there was no evidence of YFV transmission in coastal southeast Brazil before the current outbreak, nor the spread or establishment of an independent sylvatic cycle of ZIKV or urban Aedes aegypti transmission of YFV in the region. In view of the region's receptivity and vulnerability to arbovirus transmission, surveillance of NHPs and mosquitoes should be strengthened and continuous
Bay of Bengal Sea surface salinity variability using a decade of improved SMOS re-processing
No full textMonsoon rain and rivers bring large freshwater input to the Northern Bay of Bengal (BoB), yielding low Sea Surface Salinity (SSS) after the monsoon. The resulting sharp upper-ocean salinity stratification is thought to influence tropical cyclones intensity and biological productivity by inhibiting vertical mixing. Despite recent progresses, the density of in situ data is far from sufficient to monitor the BoB SSS variability, even at the seasonal timescale. The advent of satellite remotely-sensed SSS (SMOS, Aquarius, SMAP) offers a unique opportunity to provide synoptic maps of the BoB SSS every similar to 8 days. Previous SMOS SSS retrievals did not perform well in the BoB. Here, we show that improved systematic error corrections and quality control procedures yield a much better performance of the new "debiased v4" CATDS level-3 SSS from SMOS (similar to 0.8 correlation, 0.04 bias and 0.64 root-mean-square difference to more than 28,000 collocated in situ data points over 2010-2019). The SMOS product now performs equivalently to Aquarius, and is slightly inferior to SMAP over the BoB. In particular, SMAP and SMOS are able to capture salinity variations close to the east coast of India (r > 0.8 within 75-150 km of the coast). They thus capture the seasonal freshening there, associated with equatorward advection of the Northern BoB low-salinity water by the East Indian Coastal Current (EICC) after the summer monsoon. The 10-year long SMOS record further allows to describe the BoB interannual SSS variability, which is strongest in boreal fall in relation with the Indian Ocean Dipole (IOD). Positive IOD events induce a weakening of the southward export of freshwater by the EICC, and hence negative SSS anomalies in the Northern BoB and positive ones along the East Indian coast. This confirms results from earlier studies based on modelling, sparse in situ data, or shorter satellite records, but this time from a 10-year long SSS record. Overall, our study indicates that the new SMOS retrieval can be confidently used to monitor the BoB SSS and to study its mechanisms. We end by a brief description of the BoB SSS anomalies associated with the extreme 2019 IOD event and highlight the very good performance over the BoB of a new multi-satellite product developed by the European Space Agency merging SMOS, Aquarius and SMAP data
Statistical approach to evaluate effect of temperature and moisture content on the production of antioxidant naphtho-gamma-pyrones and hydroxycinnamic acids by Aspergillus tubingensis in solid-state fermentation
No full textNon-ochratoxigenicAspergillus tubingensisG131 is a filamentous fungus that can produce naphtho-gamma-pyrones (N gamma Ps), polyketide pigments that exhibit interesting antioxidant properties. This study aims to investigate the effect of two critical parameters, temperature and moisture content on the fungus grown in solid-state fermentation using agricultural by-products (vine shoots and wheat bran) as sole medium. From the kinetic productions of secondary metabolites N gamma Ps (asperpyrone E, dianhydroaurasperone C, fonsecin, fonsecin B and ustilaginoidin A), alkaloids (nigragilin and aspernigrin A), degradation products from the solid medium (beta-d-glucose,p-coumaric acid andtrans-ethyl ferulate), ergosterol and conidia obtained for different temperatures and moisture contents, a principal component analysis (PCA) was carried out to highlight the production patterns of these compounds. This approach allowed us to determine that fonsecin, the compound of higher interest-exhibiting the most interesting antiradical potential-is particularly more produced at 25 degrees C and 66% of moisture content. This study underlines the importance of temperature and moisture content on naphtho-gamma-pyrones and hydroxycinnamic acid production using solid-state fermentation and contributes to the development of agroindustrial by-product valorization