International Journal of Agricultural Research, Innovation and Technology (IJARIT)
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De l’hypermobilité généralisée à l’immobilité contrainte. Quels récits (carto)graphiques des mobilités quotidiennes en période de pandémie ?
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OS NOVOS BATUQUEIROS E O DESENCANTO DO PODER PÓS-COLONIAL Uma viagem através de "O Ocaso dos pirilampos", de Adriano Mixinge
No full textResumo "Os novos batuqueiros e o desencanto do poder pós-colonial: uma viagem através de O Ocaso dos pirilampos", de Adriano Mixinge" é um trabalho de investigação realizado no quadro de Teorias da Literatura. Trata-se de análise do romance "O Ocaso dos pirilampos", no sentido de encontrar a interpretação, do papel do batuqueiro, nome dado ao narrador-protagonista, em relação aos antigos batuqueiros. O estudo enquadra-se na literatura africana das independências, que consiste em analisar a obra em relação aos poderes dos países africanos na era das independências. Palavras-chave: Batuqueiro, poder pós-colonial, desencanto
Cost-utility analysis of four WHO-recommended sofosbuvir-based regimens for the treatment of chronic hepatitis C in sub-Saharan Africa
No full textInternational audienceBackground: Although direct-acting antivirals (DAA) have become standard care for patients with chronic hepatitis C worldwide, there is no evidence for their value for money in sub-Saharan Africa. We assessed the cost-effectiveness of four sofosbuvir-based regimens recommended by the World Health Organization (WHO) in Cameroon, Côte d'Ivoire and Senegal.Methods: Using modelling, we simulated chronic hepatitis C progression with and without treatment in hypothetical cohorts of patients infected with the country's predominant genotypes (1, 2 and 4) and without other viral coinfections, history of liver complication or hepatocellular carcinoma. Using the status-quo 'no DAA treatment' as a comparator, we assessed four regimens: sofosbuvir-ribavirin, sofosbuvir-ledipasvir (both recommended in WHO 2016 guidelines and assessed in the TAC pilot trial conducted in Cameroon, Côte d'Ivoire and Senegal), sofosbuvir-daclatasvir and sofosbuvir-ledipasvir (two pangenotypic regimens recommended in WHO 2018 guidelines). DAA effectiveness, costs and utilities were mainly estimated using data from the TAC pilot trial. Secondary data from the literature was used to estimate disease progression probabilities with and without treatment. We considered two DAA pricing scenarios: S1) originator prices; S2) generic prices. Uncertainty was addressed using probabilistic and deterministic sensitivity analyses and cost-effectiveness acceptability curves.Results: With slightly higher effectiveness and significantly lower costs, sofosbuvir/velpatasvir was the preferred DAA regimen in S1 with incremental cost-effectiveness ratios (ICERs) ranging from US632/QALY. At the cost-effectiveness threshold (CET) of 0.5 times the 2017 country's per-capita gross domestic product (GDP), sofosbuvir/velpatasvir was only cost-effective in Senegal (probability > 95%). In S2 at generic prices, sofosbuvir/daclatasvir was the preferred regimen due to significantly lower costs. ICERs ranged from US216/QALY according to country i.e. a 95% probability of being cost-effective. Furthermore, this regimen was cost-effective (probability> 95%) for all CET higher than US223/QALY and US$195/QALY in Cameroon, Côte d'Ivoire and Senegal, respectively, corresponding to 0.14 (Côte d'Ivoire and Senegal) and 0.2 (Cameroon) times the country's per-capita GDP.Conclusions: Generic sofosbuvir/daclatasvir is very cost-effective for treating chronic hepatitis C in sub-Saharan Africa. Large-scale use of generics and an increase in national and international funding for hepatitis C treatment must be priorities for the HCV elimination agenda
Interaction Between Climate and Tectonics in the Northern Lesser Antilles Inferred From the Last Interglacial Shoreline on Barbuda Island
No full textInternational audienceIn the context of increasing evidence of plate interface coupling variability in subduction zones, there is a need to extend the short time window given by instrumental data and to gather data over multiple time and spatial scales. We hence investigated the long-term topography on Barbuda island, located in the northern part of the Lesser Antilles, west of the Caribbean subduction zone. Following pioneering work using a set of marine terraces on the eastern side of the island, we performed the first U-Th dating on 10 corals in growth position from the lowest terrace, for which the highest relative sea-level (RSL) indicator is found at 9 ± 1 m above the mean sea level. We find that this terrace corresponds to the Last Interglacial (LIG) (ages between 122.8 ± 0.3 ka and 128.1 ± 0.3 ka) and we estimate a paleo RSL of 7 ± 2 m above the current mean sea level. The present elevation of the LIG shoreline on Barbuda might imply tectonics as an additional mechanism to eustatic sea level, mantle dynamic topography and glacial isostatic adjustment. East-west morphological asymmetry of Barbuda and difference in LIG shoreline elevation between Barbuda and Antigua suggest a regional tectonic process. As with the proposed westward tilting from the forearc to the volcanic arc of the Guadeloupe archipelago, vertical deformation on Barbuda could be related to plate-scale subduction processes. Long-term uplift of Barbuda might be related to the accumulation of residual coseismic deformation not fully recovered by interseismic subsidence and the corresponding seismogenic segment would extend below the Moho
Time relationship between emplacement, fabric development and regional deformation of the Manchi granitic pluton (western - Cameroon domain)-an integrated AMS, CPO and microstructural investigation
No full textInternational audienceIn this study, we integrate anisotropy of magnetic susceptibility (AMS) and microstructural data including quartz crystallographic preferred orientation (CPO) from SEM-EBSD from the Manchi Pan-African granitic pluton with the objective of deciphering the time relationship between fabric development, emplacement and regional tectonics. The Manchi pluton, located in the western Cameroon domain of the Pan-African Fold Belt of Central Africa in Cameroon, is made of hornblende-biotite granite (HBtG), biotite granite (BtG) and protomylonites of HBtG. The pluton intruded the high grade country rocks made of banded gneiss and amphibolites. AMS of the pluton is controlled dominantly by paramagnetic phases such as, Fe-bearing silicates (biotite and hornblende). This is inferred from the low Km values (-6 SI units) as well as from hysteresis data. The AMS ellipsoid shape is mostly oblate, implying that flattening component of the strain was important during granite emplacement. Microstructural observations reveal presence of magmatic to sub-magmatic and solid-state deformation textures developed at moderate- to low-temperatures. This is consistent with the presence of rhomb and basal slip systems established from quartz c-axis data through EBSD analysis. The pluton recorded top-toward SW to top-toward south sense of shear as established by the kinematic markers. This indicates a component of simple shear during tectonic evolution of the pluton. We infer that the magnetic fabrics recorded in the Manchi granitic pluton is a manifestation of the D2 regional deformation. The dominance of flattening strain and the concentric pattern of magnetic data are indicative of ballooning being an important mechanism under transpressive regime
Pollution parameters evaluation of wastewater collected at different treatment stages from wastewater treatment plant based on E-nose and E-tongue systems combined with chemometric techniques
No full textInternational audienceWastewater contains harmful chemicals and heavy metals that are known to cause various environmental and health problems. Therefore, the water quality control using sensitive, simple, fast, accurate, and portable tools is of great importance. In this study, an electronic nose (Enose) and an electronic voltammetric tongue (E-tongue) combined with chemometric methods were used for qualitative analysis of water samples collected from a wastewater treatment plant (WWTP) that treats domestic and industrial wastewaters. Quantitative determination of pollution parameters of water and wastewater samples were performed in BAM, Berlin. The inductively coupled plasma optical emission spectrometry was used for cations determination. Analysis of anions was carried out by ion chromatography with a Metrosep A Supp 5-100/4.0 column. Chemometric methods, such as Principal Component Analysis (PCA), Discriminant Function Analysis (DFA), Support Vector Machines (SVMs), and Hierarchical Cluster Analysis (HCA), were used to process the E-nose and E-tongue data to describe the similarities between the samples. In addition, Partial Least Squares Regression (PLSR) model was constructed using the E-nose and E-tongue data to simultaneously predict the levels of physicochemical parameters. Indeed, the PLSR analysis is performed generating a correlation coefficient, for the training and testing sets, higher than 0.91 for the prediction of the concentration of all physicochemical parameters, except for iron (Fe) which remains 0.84. These results suggest that simple, portable, and inexpensive tools such as electronic noses and tongues are suitable for wastewater analysis
1.2 Myr Band of Earth‐Mars Obliquity Modulation on the Evolution of Cold Late Miocene to Warm Early Pliocene Climate
No full textInternational audienceThe climatic transitions during the Miocene-Pliocene epochs had significant impacts on the worldwide biological diversity and were associated with large turnovers of continental vegetation and fauna. Previous studies have shown that late Miocene cooling and continental aridification which was initiated 7 Ma reversed to warm conditions across the Miocene-Pliocene Boundary ∼5.3 Ma. Here, we present detailed orbital pacing of Asian monsoon deposits to constrain further the global climate change during this period. We produce high-resolution magnetic susceptibility records which reveal that the 1.2 Myr obliquity modulation would have been the main driving factor of the cooling and warming that occurred ∼7 and 5.3 Ma, respectively. The Tibetan rise and closures of the Panama and Indonesian seaways enhanced the impact of the 405 Kyr eccentricity cycles to an oscillatory climatic state while the Northern Hemisphere glaciations were increasing from 4 to 2.5 Ma.
VHH Structural Modelling Approaches: A Critical Review
No full textInternational audienceVHH, i.e., VH domains of camelid single-chain antibodies, are very promising therapeutic agents due to their significant physicochemical advantages compared to classical mammalian antibodies. The number of experimentally solved VHH structures has significantly improved recently, which is of great help, because it offers the ability to directly work on 3D structures to humanise or improve them. Unfortunately, most VHHs do not have 3D structures. Thus, it is essential to find alternative ways to get structural information. The methods of structure prediction from the primary amino acid sequence appear essential to bypass this limitation. This review presents the most extensive overview of structure prediction methods applied for the 3D modelling of a given VHH sequence (a total of 21). Besides the historical overview, it aims at showing how model software programs have been shaping the structural predictions of VHHs. A brief explanation of each methodology is supplied, and pertinent examples of their usage are provided. Finally, we present a structure prediction case study of a recently solved VHH structure. According to some recent studies and the present analysis, AlphaFold 2 and NanoNet appear to be the best tools to predict a structural model of VHH from its sequence
Porosity induced by dislocation dynamics in quartz-rich shear bands of granitic rocks
No full textInternational audienceThe production of micro-pores is a driving mechanism for fluids to interact with deep environment and influence rock properties. Yet, such a porosity still remains misunderstood to occur in viscous rocks and may be attributed to either grain boundary sliding (GBS), dissolution effects or sub-grain rotation. Here we focus on quartz-rich shear bands across the Naxos western granite (Aegean Sea, Greece), where we document sub-micron pores at quartz boundaries. While most of these pores are observed along grain boundaries, some of them occur at intra-grain boundaries, which excludes dissolution or GBS to produce them, but instead involves the dynamic of dislocations. We then confirm that quartz is dominated by dislocation creep with evidence of a moderate to strong lattice-preferred orientation (LPO) and numerous tilt/twist boundaries, including at the pluton margin where rocks embrittled. These features coincide with (1) randomly oriented 'inclusion' quartz grains along tilt/twist boundaries and (2) a partial dependency of the LPO strength on grain size. Our findings suggest that pores arise from coalescing dislocations at boundaries of rotating sub-grains, providing nucleation sites for new grains to be precipitated during plastic flow. Fluid infiltration, rock embrittlement and related implications are also expected through pores accumulation with increasing strain
Tributyltin in Wastewater: Influence on the Performance of Suspended Growth Biological Processes
No full textInternational audienceThe aim of this study was to evaluate the potential effect of tributyltin (TBT) on the performance of suspended-growth biological processes. The influence of TBT was evaluated for (i) the endogenous and exogenous respirations of heterotrophic micro-organisms in laboratory-scale batch reactors, taken from a municipal wastewater treatment plant and (ii) chemical oxygen demand (COD) removal, sludge production and oxygen consumption of a pilot-sale membrane bioreactor (MBR) system inoculated with heterotrophic micro-organisms taken from a MBR system. The batch experiments showed that the presence of TBT was likely to modify the activity of bacterial populations in endogenous conditions. The increase in endogenous oxygen needs suggested an increase in the maintenance requirements, essentially to manage the chemical stress induced by the presence of TBT. If the addition of TBT did not perturb COD removal in an MBR system, it limited sludge production and increased oxygen requirements; it is assumed that these modifications were linked with the necessity for the biomass to adapt in this stressful environment, as reflected by an increase in the maintenance requirements. These results emphasised that the respiratory activity of the bacterial cultures was modified by the presence of TBT, in the sense that an excess of oxygen was required to adapt to this chemical stress.Le but de cette étude était d'évaluer l'effet potentiel du tributylétain (TBT) sur la performance des processus biologiques à croissance suspendue. L'influence du TBT a été évaluée pour (i) les respirations endogène et exogène de micro-organismes hétérotrophes dans des réacteurs batch à l'échelle du laboratoire, provenant d'une station d'épuration municipale et (ii) l'élimination de la demande chimique en oxygène (DCO), la production de boues et la consommation d'oxygène d'un système pilote de bioréacteur à membrane (MBR) inoculé avec des micro-organismes hétérotrophes provenant d'un système MBR. Les expériences en batch ont montré que la présence de TBT était susceptible de modifier l'activité des populations bactériennes en conditions endogènes. L'augmentation des besoins endogènes en oxygène a suggéré une augmentation des besoins de maintenance, essentiellement pour gérer le stress chimique induit par la présence de TBT. Si l'ajout de TBT n'a pas perturbé l'élimination de la DCO dans un système MBR, il a limité la production de boues et augmenté les besoins en oxygène ; on suppose que ces modifications sont liées à la nécessité pour la biomasse de s'adapter dans cet environnement stressant, comme le reflète l'augmentation des besoins de maintenance. Ces résultats ont souligné que l'activité respiratoire des cultures bactériennes était modifiée par la présence de TBT, dans le sens où un excès d'oxygène était nécessaire pour s'adapter à ce stress chimique