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Changes in Cooking and Breadmaking Properties of IR 841 Paddy Rice During Storage in West Africa
No full textInternational audienceTemperature and relative humidity can significantly affect quality of paddy rice during storage. Limited studies established the link between storage time, environmental fluctuations, changes in grain and flour physicochemical properties, and culinary performances. In a West African context, IR 841 paddy rice variety was stored under humid-sub-humid (HSH), and dry (DRY) conditions for 12 months. Over 12 months, rice stored under DRY conditions experienced greater environmental fluctuations than rice stored under HSH conditions. Grain water absorption capacity (WAC) increased during storage under DRY conditions, rising from 3.3 ± 0.3 to 3.8 ± 0.3 g/g DM between 0 and 12 months. Flour amylose content and soluble solids remained relatively stable from month 0 to 6 in all conditions, and further under HSH conditions. The observed changes led to improved grain cooking performance after 6 months of storage under DRY conditions. After 12 months, a decrease in rice flour WAC and a peak in viscosity were observed, while mean particle size increased from 42 ± 1 to 67 ± 3 µm under HSH conditions and from 31 ± 3 to 83 ± 3 µm under DRY conditions. Storage time may reduce the breadmaking capacity of rice flour. Overall, environmental fluctuations under DRY conditions strongly affected rice grain and flour properties.</div
Zero-inflated binary Tree Pólya splitting regression for multivariate count data
No full textSpecies distribution models (SDMs) are widely used to assess the effects of environmental factors on speciesdistributions. However, classical SDMs ignore inter-species dependencies. Multivariate SDMs (MSDMs), especially those basedon latent Gaussian fields such as the multivariate Poisson log-normal (MPLN), address this limitation but face challengesrelated to computation, dimensionality, and interpretability. Pólya-splitting (PS) distributions offer an alternative, combininga model for total abundance with a multivariate allocation structure, and have natural interpretations from ecological processmodels. Yet, they lack flexibility in modeling correlation structures. Tree Pólya-splitting (TPS) distributions overcome thisby introducing hierarchical structure such as a phylogenetic tree. In this paper, we extend TPS to account for zero-inflation,leading to the zero-inflated tree Pólya-splitting (Z-TPS) family. We detail its statistical properties, show how standard softwareenables efficient inference, and illustrate its ecological relevance using tree abundance data from over 180 genera across theCongo Basin tropical rainfores
The North Balearic Front as an ecological boundary: zooplankton fine-scale distribution patterns in late spring
No full textInternational audienceObservations, models and theory have suggested that ocean fronts are ecological hotspots, generally associated with higher diversity and biomass across many trophic levels. Nutrient injections are often associated with higher chlorophyll concentrations at fronts, but the response of the zooplankton community is still insufficiently understood. The present study investigates mesozooplankton stocks and composition during late spring, northeast of Menorca, along two north-south transects that crossed the North Balearic Front separating central waters of the Northwestern Mediterranean Sea gyre from peripheral waters originating from the Algerian basin. During the BioSWOT-Med campaign, vertical triple-net tows with 200 and 500 µm meshes were carried out at three depths (100, 200, and 400 m), and the samples were processed with ZooScan to classify organisms into eight taxonomic groups. Zooplankton distributions were analyzed for the surface layer (0–100 m), a mid-depth layer (100–200 m), and a deeper layer (200–400 m). The results did not show a significant increase in biomass in the front in any layers. The NBF appears to act as a boundary between communities rather than a pronounced area of active or passive zooplankton accumulation. Analyses of stratified vertical distributions of zooplankton highlighted distinct taxonomic compositions in the three layers, and a progressive homogenization of community structure with depth, reflecting a weaker impact of hydrological processes on deeper communities. The clearest impact of the front was within the upper 100 m, where the mesozooplanktonic taxonomic composition differed between the front and adjacent water masses, with a decrease in all taxonomic groups except Cnidaria, which increased dramatically. In the two deeper layers, the front also influenced community composition, although to a lesser extent, with marked increases in Foraminifera and Cnidaria. Moreover, the northern water mass and the front were dominated by large copepods, while the southern water mass exhibited higher zooplankton diversity and smaller-sized copepods. The results of this study highlight the complexity of processes shaping planktonic communities over time and space in the NBF zone and its adjacent waters. These processes include zooplankton stock reduction in the transitional post-bloom period, marked effect of diel variation linked to vertical migrations, and potentially the impact of storm-related mixing in the surface layer that can disrupt established ecological patterns
INTERMEDIATE RESISTANCE AND CAPACITANCE STATES IN Ge-RICH GeSbTe PHASE CHANGE MEMORY
No full textInternational audienceWe investigate intermediate states of Ge-rich GeSbTe phase-change memory cells by electrical impedance spectroscopy after partial SET and RESET programming. The impedance response is well described by a series resistor and a parallel RC circuit, allowing extraction of state-dependent resistance and capacitance values. A resistance contrast of and a capacitance reduction of are observed between RESET and SET states. While resistance can be continuously tuned, capacitance major variation remains confined near the SET state, with crystalline-dominated cells exhibiting the highest values. Technology Computer-Aided Design simulations confirm the equivalent circuit and reveal that conduction mainly occurs along the amorphouscrystalline interface. Cells with embedded Ge or Sb grains display the largest capacitances, as these inclusions provide extra conduction pathways and localized charge storage sites that jointly influence the device's resistance and capacitance. Overall, this work demonstrates that the electrical properties of inhomogeneous multiphase PCMs are governed by the complex network of nanoscale heterostructures present in their active regions. It also demonstrates that impedance spectroscopy is a suitable, non-destructive technique for characterizing PCM devices.</div
Towards a Narrative Change? New Archaeobotanical Research on the ‘Green Revolution’ at the Heartlands and Frontiers of al-Andalus
No full textInternational audienceThis study documents the diversity of Andalusi agricultural production and practices in different regions of the Iberian Peninsula between the 11th and the 14th centuries, based on unpublished case studies from the “Landscapes of (Re) Conquest” project and pre-existing published data. At the heart of this research lies the question of agricultural innovations that are widely associated in the scholarly literature with the Arab-Berber expansion across Iberia. The most recent overviews spoke for themselves: none of the crops of the medieval ‘green revolution’ mentioned in the texts (e.g. cotton, sugarcane, spinach, eggplant, etc.) had been discovered (Peña-Chocarro et al. 2019; Ros et al. 2019), and it is only in the last two years that new taxa (e.g. citrus fruits, rice) have begun to appear in Andalusi archaeological contexts in Iberia , on a very occasional basis (Peña-Chocarro and Pérez-Jorda 2023; Peña-Chocarro et al. 2024). These data raise the question of the real expansion of Arab-Berber agriculture in the West, and of the “new plants” and their rhythm of diffusion: was this really a uniformly widespread phenomenon throughout the entire medieval Muslim West? Or was it limited to the landed estates of the urban aristocracy and to the large areas of specialized production (e.g. al-Andalus), well known from written sources? Focusing on Iberia, did the areas at the frontiers of Andalusi territories continue to practice agriculture that was strictly identical to that of the Roman and/or Visigothic periods? Or did they experience similar trends to those in neighbouring Christian territories, i.e. a boom in rye and certain spring crops (e.g. millets, flax, hemp) (Ros et al. 2023)? This innovative research lays the foundations for a new reflection on the persistence and evolution of the production and management of plant resources in the face of the major political, social and economic changes that took place in the Peninsula during the medieval period. They also highlight an otherwise neglected topic in the field of archaeobotany – the contrasting agrarian dynamics of political heartlands and frontiers
Environmental consequences of genetic improvements of growth and fillet yield in gilthead seabream: A life cycle assessment from breeding to plate
No full textInternational audienceSelective breeding plays a key role in the sustainable development of aquaculture by improving productivity and efficiency. While breeding programs have initially focused on growth traits, their potential to mitigate the environmental footprint of fish farming remains poorly explored. Here, we present a case-study on the environmental consequences of selective breeding during five generations (15 years) for growth and fillet yield in gilthead sea bream Sparus aurata by integrating genetic gain projections into a full supply chain Life Cycle Assessment (LCA), extending from hatchery to final consumer. The potential impacts were calculated in terms of 1 tonne of fish produced at the farm level and were also expressed per tonne of flesh consumed. Performance data and genetic parameters from families in a seabream breeding program were used to estimate breeding values under different selection scenarios. Selection for growth significantly shortened the production cycle, while selection for fillet yield increased the proportion of edible product. Although environmental gains at the farm level were modest (<1 %), substantial reductions (up to 7 % in climate change impacts and cumulative energy demand) were observed when impacts were expressed per tonne of fillet consumed. Feed production and consumption remained the dominant source of environmental burden across all scenarios. By explicitly accounting for post-farm stagesprocessing, distribution, consumption, and waste management -our study demonstrates that genetic improvement, particularly for fillet yield, can meaningfully reduce the environmental footprint of aquaculture products delivered to the consumer. This case study underlines the importance of integrating full supply chain assessments into genetic selection strategies to drive sustainable breeding in aquaculture
Opportunities from energy-loss near-edge fine structure analysis to track chemical and structural damage in zircon
No full textInternational audienceZircon (ZrSiO4) is the oldest-known mineral of Earth and an ubiquitous silicate in geochronology. More specifically, the accumulation of alpha decay damage in zircon over time significantly affects its physical and chemical properties, and can lead to a disturbance of the ages measured in this mineral. Therefore, analytical tools that enable comprehensive structural and chemical information at the nanoscale in this compound are highly sought after. In this context, we explore the electron energy-loss fine structures resulting from the excitation of O1s and Si2p core electrons in zircon, which are interpreted from ab initio calculations in a single-particle framework. An excellent agreement is obtained between the experimental and calculated fine structures, emphasizing the large distortion of the final electronic states induced by the core-hole potential. The O-K edge is particularly rich in information, with intense peaks dominated by O2p - Zr4d and O2p - Si3sp hybrids. This work suggests that the near-edge structures from the O1s and Si2p excitations accessible from electron energy-loss spectroscopy or X-ray absorption spectroscopy could be used as tools to follow, interpret and understand structural and chemical modifications in zircon subject to natural radiation damage. We illustrate the potential of this approach through the evolution of near-edge fine structures in a zircon sample that exhibits a locally amorphized zone formed by ultrafast laser excitation
Exner diagnosis method for two-fluid morphodynamics simulations
No full textInternational audienceMass balance in sediment transport is often associated with single-phase flow model through the resolution of the Exner equation. In this contribution, the mass balance is derived from the two-phase flow, two-fluid, model equations and compared with the conventional single-phase flow approach. Five terms are identified from the two-phase flow formulation: the bed evolution, the storage evolution, the lateral flux, the bed flux and the top flux. Three different flow configurations with increasing complexity are tested, namely a one dimensional pure sedimentation, a two dimensional scour downstream an apron and a three dimensional scour around a vertical square cylinder. The mass balance formulation identifies the driving process of an erosion or a deposition process in each case. This approach can be applied on other configurations related with sediment flux and morphology bed evolution such as scour process
Growth, metabolic, and immune responses of lean and fat rainbow trout lines during a starvation-refeeding cycle
No full textInternational audienceUnderstanding how fish with divergent energy reserve profiles respond to feed deprivation is critical for optimizing aquaculture feeding strategies. In this study, we compared two rainbow trout (Oncorhynchus mykiss) lines selected for low (lean, L) or high (fat, F) muscle lipid content. Both lines underwent a 3-week starvation period followed by 3 weeks of refeeding using self-feeders. The L line exhibited faster post-refeeding growth, higher post-refeeding weight gain, and earlier feeding activity concentrated in the morning. Conversely, the F line showed greater weight loss during starvation, reduced haematocrit and innate immune parameters, and limited metabolic recovery. Starvation induced distinct changes in lipid and protein metabolism, hydromineral regulation, and immune responses, with the F line being more metabolically and immunologically impacted. Plasmatic concentrations of calcium and sodium decreased, while chlorides concentrations increased transiently. Principal Component Analysis revealed stronger physiological disruption in the F line during starvation. These findings highlight how fat reserves influence recovery from nutritional stress, offering perspectives for genotype-specific feed management in aquaculture