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Pregnancy chances and obstetrical outcomes after egg donation according to the maternal indication
No full textInternational audienceIntroductionInfertility constitutes a major public health issue, and requests for oocyte donation, initially indicated in cases of premature ovarian insufficiency or to avoid the transmission of a maternally inherited genetic disease, are currently increasing due to the rise in requests following IVF failure or in cases of age-related infertility. Pregnancies resulting from oocyte donation are associated with increased obstetric morbidity compared with spontaneous pregnancies or those resulting from IVF with autologous oocytes. However, the influence of the initial indication for oocyte donation on obstetric outcomes is still debated.ObjectiveTo evaluate clinical pregnancy rates and obstetric outcomes of singleton pregnancies after oocyte donation according to the maternal indication.Materials and MethodsA retrospective single-center study including infertile women aged 18 to 43 years, managed with oocyte donation between 2012 and 2024 in our Assisted Reproductive Technology center. Clinico-biological data and the outcomes of oocyte donation cycles were analyzed. The obstetric outcomes of singleton ongoing pregnancies were studied according to the etiology of oocyte donation: group 1 (intra-couple IVF failure), group 2 (genetic cause), group 3 (idiopathic POI), group 4 (iatrogenic POI).ResultsA total of 276 women underwent 586 oocyte donation cycles, with embryo transfer performed in 88% of cases under hormone replacement therapy. The clinical pregnancy rate per cycle was 30%, significantly higher in the group 3 idiopathic POI (44.2%,). The live birth rate per cycle was 21% in the overall population and 31% in the group 3 (p = 0.014). Among the 107 singleton pregnancies resulting in live birth, the most frequent complications were gestational diabetes (23 %) and hypertensive disorders (23%), with no significant difference between the 4 groups. The overall caesarean section rate was 44%.ConclusionPatients with idiopathic POI achieve better pregnancy and live birth rates after oocyte donation, without a specific increase in obstetric complications compared with other indications. The increased obstetric morbidity observed after oocyte donation underlines the need for personalized pregnancy follow-up
Landscape Structure Shapes the Equilibrium Between Migratory and Sedentary Species in Avian Breeding Communities Along an Altitudinal Gradient
No full textInternational audienceAim Human land use shapes landscapes and threatens avian biodiversity, yet its interaction with altitudinal gradients and the consequences for the assembly of long‐distance migratory and sedentary bird communities remain poorly understood. Location Southern France. Taxon Avian breeding communities. Method We examined the changes in the migratory–sedentary ratio (the relative proportion of migratory versus sedentary species) in avian breeding communities (5 × 5 km resolution) in response to a regional‐scale altitudinal gradient (4000 m), in interaction with landscape structure (landscape heterogeneity and forest cover) and species richness. Results We detected interactions between altitude, landscape structure and species richness influencing the migratory: sedentary ratio. This highlights the complex responses of avian communities to both abiotic and biotic drivers. Reduced habitat diversity and evenness at lower altitudes promoted the occurrence of migratory species. While increasing forest cover generally promotes bird species richness, our results showed that its effect on the migratory: sedentary ratio differ between altitudinal belts. Specifically, forest cover was associated with a decrease in the proportion of migratory species at lower altitudes but with an increase at higher altitudes. Finally, increasing total bird richness altered the equilibrium at lower altitudes, where the richest communities (above ~117 bird species) hosted more migratory species than expected from the regional pool. We hypothesise that adding migratory rather than sedentary species to the richest communities reduces competitive interactions for resources and limits niche saturation. Main Conclusions Understanding interactions among environmental drivers is essential for predicting the assemblage of avian communities. Our results identify specific environmental conditions that promote or threaten the richness of migratory and sedentary bird species and thus provide insights to inform conservation actions and policy decisions aimed at mitigating the impacts of environmental change on avian communities
Understory plant indicator values poorly perform at monitoring temporal changes in French forest soil chemical properties
No full textInternational audienceUnderstory plant communities are widely used to infer soil conditions through species indicator values (IVs), scores reflecting species’ ecological preferences for factors such as soil acidity, moisture, or nutrient levels. While their reliability to describe soil conditions along spatial gradients is well established, their ability to capture temporal changes in soil chemistry remains largely untested at both temporal and geographical scales. We combined 26 years of vegetation monitoring with two French national soil surveys (1993–1997; 2007–2012) across 102 permanent forest plots to assess the reliability of community soil indices (CSIs) as bioindicators of soil pH, carbon-to-nitrogen ratio (C/N), and extractable phosphorus. CSIs were computed by averaging species IVs for each plot and survey. Temporal dynamics of measured soil properties and CSIs were analyzed using mixed-effects models at the national scale, while local trends were estimated separately for each plot to directly compare measured and vegetation-inferred changes. CSIs showed strong spatial correlations with measured pH and C/N, but weaker relationships for phosphorus. In contrast, no significant coupling was found between temporal changes in CSIs and measured soil parameters, with frequent mismatches in both direction and magnitude at the plot level. Measured soil dynamics were mainly driven by initial edaphic conditions and stand age, whereas CSI dynamics responded primarily to canopy openness and anthropogenic disturbances such tree harvesting. These findings confirm the value of IVs for spatial bioindication but highlight their limited sensitivity for detecting long-term soil changes, especially where soil changes remain modest
Correlational analysis of distinct contributions and overlaps between visual, visual attention, and perceptual spans
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Le Poste de Lecture Assisté par Ordinateur (PLAO) : une utopie numérique
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Assessment of biophysical properties of mango purées from whole-fruit NIRS of different varieties
No full textSource Agritrop Cirad (https://agritrop.cirad.fr/616408/) * Autres projets (id;sigle;titre): ;SADUR;(FRA) Systèmes Alimentaires Durables en milieu insulaire//International audienceThis work combined multi-variety, multi-ripening stages with non-destructive Near-Infrared Spectra (NIRS) modeling to predict processed mango purée quality traits. 2083 fruits were analyzed by non-destructive texture and NIRS measurements, and then processed into 240 purées. The quality traits of 61 representative purées were characterized. The performance of partial least-square regression (PLS) models was evaluated to predict the purées' dry matter (DM), total soluble solids (TSS), pH, titratable acidity (TA), color (L∗, a∗, b∗), rheological parameters (flow indices n, consistency index K, flow point ɣf, elastic and viscous moduli (G'LVE and G"LVE)), and granulometric parameters (statistical diameters D [3; 2] and D [4; 3]). Cogshall purées had the highest n, and the lowest G'LVE, G"LVE and D [3; 2] values. Modelling highlighted that ripening was the only factor modulating D [3; 2], whereas ɣf was variety-dependent. The fruit NIRS PLS models with RPD value > 2.5 for DM, G'LVE, while G"LVE and ɣf demonstrated good/excellent performance. For TSS, b∗, D [3;2] and D [4;3] satisfactory quantitative prediction was obtained (2 < RPD <2.5). Finally, NIRS presented poor predictive performance for pH, AT, L∗, a∗, n and k. These findings should be extended to other varieties and production systems to achieve higher representativity and genericity
Adaptive effects of geographic origin on tree ring width and radial growth -climate relationships in Pinus nigra Arnold, the European black pine
No full textRadial growth is an adaptive trait that is expected to vary among forest tree populations when habitat conditions change. Pinus nigra J.F. Arnold (1785), the European black pine, is a forest tree species widely but patchily distributed throughout southern Europe, from isolated locations in north Africa to the Black Sea and Western Asia. While it has been widely used as plantation species since the mid-19 th century because of its strong growth on rather poor soils, the effect of genetic lineages and geographic origins on mean ring widths has not yet need assessed. In this study, we analyze the radial growth performance of sixteen different geographic origins (provenances) of P. nigra growing in four bioclimatically contrasted common gardens in France.Using a tree-ring to climate relationship approach and a 40-year long chronology, we first estimated how variable the effect of monthly climate was on radial growth, depending on phylogenetic or geographic origin, and plantation habitat. We then used the tree ring data to estimate genetic and plasticity effects and to test for the existence of genotype by environment interactions. Lastly, we ranked the growth performance of the different subspecies and provenances measured in each common garden, having in mind a typology for forest management.Results showed few climate effect differences among provenances and subspecies, with late spring minimum temperatures affecting radial growth negatively and early summer precipitations positively, overall. Winter maximum temperatures affected radial growth differently depending on the site, with a negative correlation at the warmest sites and a positive correlation at the coldest one. The provenance effect was stronger than the subspecies effect and radial growth phenotypic plasticity was high across the four sites (up to 50% increase in mean tree ring width from low to high fertility sites). While some provenances of P.n. subsp. pallasiana, P.n. subsp. laricio and P.n. subsp. nigra performed well in all sites, others attributed to the same subspecies displayed significant genotype by environment interactions.Provenances of the subspecies P.n. subsp. salzmannii often displayed the smallest mean ring widths except in the least fertile test site.Provenance variability within subspecies and not just subspecies variability should be considered in plantation forestry, both for restoration and timber production