Journal of Next-Generation Research 5.0
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Preliminary results from the FARCE 2015 campaign: multidisciplinary study of the forest–gas–aerosol–cloud system on the tropical island of La Réunion
No full textInternational audienceThe Forests gAses aeRosols Clouds Exploratory (FARCE) campaign was conducted in March-April 2015 on the tropical island of La Réunion. For the first time, several scientific teams from different disciplines collaborated to provide reference measurements and characterization of La Réunion vegetation, volatile organic compounds (VOCs), biogenic VOCs (BVOCs), (bio)aerosols and composition of clouds, with a strong focus on the Maïdo mountain slope area. The main observations obtained during this 2-month intensive field campaign are summarized. They include characterizations of forest structure, concentrations of VOCs and precursors emitted by forests, aerosol loading and optical properties in the planetary boundary layer (PBL), formation of new particles by nucleation of gas-phase precursors, ice-nucleating particles concentrations, and biological loading in both cloud-free and cloudy conditions. Simulations and measurements confirm that the Maïdo Observatory lies within the PBL from late morning to late evening and that, when in the PBL, the main primary sources impacting the Maïdo Observatory are of marine origin via the Indian Ocean and of bio-genic origin through the dense forest cover. They also show that (i) the marine source prevails less and less while reaching the observatory; (ii) when in the PBL, depending on the lo-calization of a horizontal wind shear, the Maïdo Observatory can be affected by air masses coming directly from the ocean and passing over the Maïdo mountain slope, or coming from inland; (iii) bio-aerosols can be observed in both cloud-free and cloudy conditions at the Maïdo Observatory; (iv) BVOC emissions by the forest covering the Maïdo mountain slope can be transported upslope within clouds and are a potential cause of secondary organic aerosol formation in the aqueous phase at the Maïdo Observatory; and (v) the simulation of dynamics parameters, emitted BVOCs and cloud life cycle in the Meso-NH model are realistic, and more advanced Meso-NH simulations should use an increased horizontal resolution (100 m) to better take into account the orography and improve the simulation of the wind shear front zone within which lies the Maïdo Observatory. Using various observations and simulations, this work draws up an inventory of the in situ studies that could be performed in La Réunion and at the Maïdo Observatory. It also aims to develop scientific collaborations and to support future scientific projects in order to better understand the forest-gas-aerosol-cloud system in an insular tropical environment
Potentiel antioxydant de Lentinula edodes (Shiitake) issu de différents modes de culture
No full textInternational audiencecommunication orale 3
An experimental test for the mass independent isotopic fractionation mechanism proposed for ozone
No full textInternational audienceOzone exhibits large and mass independent isotopic fractionations (MIF) in oxygen isotope ratios relative to molecular di-oxygen (O2) from which it is formed. An interpretation of this effect was proposed based on the behavior of the indistinguishable isotopes 16O in scattering processes. We report here an experiment aimed at testing one of the predictions of this model.O3 was formed by high frequency discharge in O2 with pressures ranging between 1.6 and 38 Torr. The isotopic evolution of the closed O2 reservoir was monitored during its distillation taking place during the continuous removal of ozone by condensation. Its composition evolves from a mass independent to a mass dependent fractionation along with the decrease in pressure. The isotopic pathways defined by this evolution in the 3 isotopes diagram are in quantitative agreement with the theoretical prediction of the disappearance of MIF with the increase of the complex lifetime stabilized as ozone
Incipient bedforms in a bidirectional wind regime
No full text27 pages, 12 figuresInternational audienceMost terrestrial sand seas form at `horse' latitudes, where the wind direction exhibits seasonal variation. Here, we extend the two-dimensional linear stability analysis of a flat sand bed associated with a unidirectional wind to the three-dimensional case in order to account for multidirectional wind regimes. Focusing on the simplest case of bidirectional flow regimes, we show that the transition from transverse to oblique or longitudinal patterns is controlled by the transport ratio and the divergence angle between the two flows. Our predictions agree with previous results for dune orientation, and also provide a wider range of possible alignments depending on flow strength, especially when the two winds are perpendicular, at which the transition occurs. This analysis also predicts the selected pattern wavelength, which either decreases close to the transition angle for strong winds, due to a geometric effect, or increases at low winds, when the bed slope affects the transport. This theoretical analysis is complemented by analogous subaqueous experiments, where bedforms are submitted to alternate water flows. For transverse bedforms, the experimental data validate the model at strong flows, providing evidence for the predicted geometric effect, but also for the increase of the wavelength close to the transport threshold. For longitudinal bedforms, a discrepancy is observed, which we interpret as the sign of enhanced nonlinearities induced by the development of slip faces when the flow alternately blows on both sides of the dune
Influence of different sources of vegetable, whey and microalgae proteins on the physicochemical properties and amino acid profile of fresh pork sausages
No full textInternational audienceThe purpose of this study was to evaluate changes in the physicochemical properties and amino acid profiles of pork sausages prepared by including vegetable protein sources (beans, peas, and lentils), microalgae (Chlorella and Spirulina) or whey, as compared with a control (soy protein). Significant differences were found for all the studied parameters. The protein content was significantly lower in sausages made with pea protein compared with the control. Colour parameters changed significantly after the incorporation of microalgae proteins. Moreover, significant differences among treatments were observed in the amino acid profile. The inclusion of Spirulina proteins resulted in an increase in the total amino acid content and the ratio of essential/non-essential amino acids. Orthogonal Projections to Latent Structures Discriminant Analysis (OPLS-DA) allowed pork sausages to be classified according to the protein source, in comparison with soy (control). Textural parameters (chewiness, gumminess and hardness) followed by colour and pH were the most discriminant parameters. Considering texture traits, physicochemical parameters and amino acid profiles across treatments, proteins from legumes and whey provided profiles closer to that of soy. However, although microalgae-derived proteins altered the colour and texture, they provided nutritionally favourable profiles, thus suggesting that seaweeds could also be used to enrich pork sausages, as an alternative to soy protein
The Pan-African post-collision Hosséré Mana plutonic complex and associated Gapi Stock (Western Cameroon Domain, Cameroon): Petrology, mineralogy and geochemistry
No full textInternational audienceIn the Cameroon Pan-African orogenic belt, the West Cameroon Domain (WCD) is characterized by the apparent lack of Archean-Paleoproterozoic relicts, the development of Neoproterozoic basins and abundant plutonic massifs. The Hosséré Mana plutonic complex (HMPC) and the Gapi gabbroic stock are located in the vicinity of the Cretaceous Ngaou Boh granite complex and the Neogene Tchabal Gangbada basanite-trachyte-rhyolite volcanic plateau. They comprise clinopyroxene + amphibole ± olivine leucogabbro, clinopyroxene + amphibole monzogabbro, biotite + amphibole ± clinopyroxene monzodiorite, porphyritic and foliated biotite ± muscovite monzogranite. Two parallel trends of Mg#, displayed by leucogabbro (0.66–0.61) - monzogabbro (0.57–0.37), and by monzodiorite (0.66–0.55) -monzogranite (0.47–0.33), evidence two contrasting igneous suites, magnesian tholeiitic and magnesian high-K alkali-calcic to calc-alkaline (I-type). Primitive mantle-normalized patterns of the tholeiitic suite are fractionated, with no significant HFSE anomalies, suggesting a garnet-bearing enriched peridotite source. Primitive mantle-normalized patterns of the high-K alkali-calcic to calc-alkaline suite include more fractionated felsic types and display NbTa negative anomalies, suggesting another source with amphibole - garnet in the residue and possible origin of felsic rocks by partial melting of mafic lower crust with garnet and titanite-rutile in the residue. In leucogabbro, fairly low Sri (0.70538) and little negative εNd(750 Ma) (+0.2), with a TDM single-stage Nd model age of 1.42 Ga, are consistent with magmas extracted near the lithosphere – asthenosphere boundary from an enriched mantle source close to BSE (Bulk Silicate Earth). In monzodiorite, little higher Sri (0.70628) and strongly negative εNd(560 Ma) (−8.8), with a TDM single-stage Nd model age of 1.64 Ga, point to a supplementary (lithospheric?) mantle source metasomatized by subduction products. HMPC and GS massifs, emplaced in a syn-to post-kinematic environment after the major collision stage, illustrate coeval magnesian tholeiitic and magnesian high-K alkali-calcic calc-alkaline (I-type) igneous suites, in which primary magmas were tapped from different mantle sources, followed by younger felsic suite issued from garnet-bearing lower crustal source
Mujeres en movimiento: historias, conflictos y escrituras (Perú, siglos XIX- XXI)
No full textURL : http://publis-shs.univ-rouen.fr/eriac/index.php?id=39
Fission-Track Thermochronology Applied to the Evolution of Passive Continental Margins
No full textInternational audiencePassive continental margins (PCMs) form at divergent plate boundaries in response to continental breakup and subsequent formation of new oceanic basins. The onshore topography of PCMs is a key component to understand the evolution of extensional settings. The classic nomenclature of PCMs is derived from early investigations that suggested apparent tectonic stability after the initial phase of rifting and breakup. However, geological and geomorphic diversity of PCMs requires more complex models of rift and post-rift evolution. Fission-track (FT) thermochronology provides appropriate tools to decipher the long-term development of PCM topography and better resolve the spatial and temporal relationships between continental erosion and sediment accumulation in adjacent offshore basins. FT datasets have revealed complex spatial and temporal denudation histories across some PCMs and have shown that several kilometres of material may be removed from the onshore margin following rifting. Combining these data with geological and geomorphological observations, and with predictions from numerical modelling, suggests that PCMs may have experienced significant post-rift activity. Case histories illustrated in this chapter include the PCM of southeastern Africa and the conjugate PCMs of the North and South Atlantic
Le livre à Saint-Paul et à Saint-Pierre (1815-1848)
No full textThe study of the book in the inventories after death concerns only a part of the population, because the notary’s services are expensive. We can ask ourselves this question: What is the place of the book in post-death inventories? To answer this question, we have at our disposal two cities, Saint-Pierre and Saint-Paul from 1815 to 1848. The presence of a library during the last possession is paramount. Each individual leaves behind a legacy through this library. A library defined by its weight, more or less consequent. The weight of the libraries being equal to the quantity of book, a book corresponds to a volume.L’étude du livre dans les inventaires après décès concerne seulement une partie de la population, car les services du notaire sont coûteux. Nous pouvons nous poser cette question : quelle est la place du livre dans les inventaires après décès ? Pour répondre à cette question, nous avons à notre disposition deux villes, Saint-Pierre et Saint-Paul, de 1815 à 1848. La présence de bibliothèques lors de la dernière possession est primordiale. Chaque individu laisse derrière lui un héritage à travers cette bibliothèque. Une bibliothèque se définissant par son poids, plus ou moins conséquent. Le poids des bibliothèques étant égal à la quantité de livres, un livre correspond à un volume