Long-Term Spatiotemporal Variability of Whitings in Lake Geneva from Multispectral Remote Sensing and Machine Learning

Whiting events are massive calcite precipitation events turning hardwater lake waters to a milky turquoise color. Herein, we use a multispectral remote sensing approach to describe the spatial and temporal occurrences of whitings in Lake Geneva from 2013 to 2021. Landsat-8, Sentinel-2, and Sentinel-3 sensors are combined to derive the AreaBGR index and identify whitings using appropriate filters. 95% of the detected whitings are located in the northeastern part of the lake and occur in a highly reproducible environmental setting. An extended time series of whitings in the last 60 years is reconstructed from a random forest algorithm and analyzed through a Bayesian decomposition for annual and seasonal trends. The annual number of whiting days between 1958 and 2021 does not follow any particular monotonic trend. The inter-annual changes of whiting occurrences significantly correlate to the Western Mediterranean Oscillation Index. Spring whitings have increased since 2000 and significantly follow the Atlantic Multidecadal Oscillation index. Future climate change in the Mediterranean Sea and the Atlantic Ocean could induce more variable and earlier whiting events in Lake Geneva

Transient development of ovotestes in XX Sox9 transgenic mice

AbstractThe sex of an individual results from the paternal transmission of the SRY gene located on the Y chromosome. In turn, SRY initiates Sox9 expression, a transcription factor required for testicular differentiation. Ectopic activation of SOX9 in XX Wt1:Sox9 transgenic mice induces female-to-male sex reversal in adult mice. Here we show that complete sex reversal is preceded by a transient phase of ovotestis differentiation with XX Wt1:Sox9 transgenic gonads containing a testicular central region and one or both ovarian poles indicating that Wt1:Sox9 is not as efficient as Sry to induce male development. In XX Wt1:Sox9Tg/+ gonads, transgenic Sox9 is expressed earlier than Sox9 in XY gonads and is able to induce the expression of EGFP, knocked into the 3′ UTR of Sox9 indicating that SOX9 is involved in the initiation and maintenance of its own expression. However, the delayed onset of expression of endogenous Sox9–EGFP suggests that this activation requires other factors, whose expression depends on SOX9. In the testicular regions of the XX Wt1:Sox9 ovotestes, proliferation of the XX fetal germ cells is hampered and they differentiate as pro-spermatogonia. This indicates that XX germ cells are not competent to respond to proliferative signals released from a testicular environment. In the ovarian regions, despite the continuous mRNA expression of the WT1:Sox9 transgene, the SOX9 protein does not accumulate suggesting that regulation of this gene in ovarian cells involves post-transcriptional mechanisms. Finally, ovarian cells of the XX Wt1:Sox9 ovotestis undergo apoptosis during late embryogenesis leading to complete female-to-male sex reversal of the transgenic mice at birth

Myocardial-specific R-spondin3 drives proliferation of the coronary stems primarily through the Leucine Rich Repeat G Protein coupled receptor LGR4

Coronary artery anomalies are common congenital disorders with serious consequences in adult life. Coronary circulation begins when the coronary stems form connections between the aorta and the developing vascular plexus. We recently identified the WNT signaling modulator R-spondin 3 (Rspo3), as a crucial regulator of coronary stem proliferation. Using expression analysis and tissue-specific deletion we now demonstrate that Rspo3 is primarily produced by cardiomyocytes. Moreover, we have employed CRISPR/Cas9 technology to generate novel Lgr4-null alleles that showed a significant decrease in coronary stem proliferation and thus phenocopied the coronary artery defects seen in Rspo3 mutants. Interestingly, Lgr4 mutants displayed slightly hypomorphic right ventricles, an observation also made after myocardial specific deletion of Rspo3. These results shed new light on the role of Rspo3 in heart development and demonstrate that LGR4 is the principal Rspondin 3 receptor in the heart

Removal of pesticide mixtures in a stormwater wetland collecting runoff from a vineyard catchment.

International audienceWetlands can collect contaminated runoff from agricultural catchments and retain dissolved and particle-laden pesticides. However, knowledge about the capacity and functioning of wetland systems with respect to the removal of pesticides is very limited. Here we show that stormwater wetlands can efficiently remove pesticides in runoff from vineyard catchments during the period of pesticide application, although flow and hydrochemical conditions of the wetland largely vary over time. During the entire agricultural season, the inflowing load of nine fungicides, six herbicides, one insecticide and four degradation products was 8.039g whereas the outflowing load was 2.181g. Removal rates of dissolved loads by the wetland ranged from 39% (simazine) to 100% (cymoxanil, gluphosinate, kresoxim methyl and terbuthylazine). Dimethomorph, diuron, glyphosate, metalaxyl and tetraconazole were more efficiently removed in spring than in summer. More than 88% of the input mass of suspended solids was retained, underscoring the capability of the wetland to trap pesticide-laden particles via sedimentation. Only the insecticide flufenoxuron was frequently detected in the wetland sediments. Our results demonstrate that stormwater wetlands can efficiently remove pesticide mixtures in agricultural runoff during critical periods of pesticide application, although fluctuations in the runoff regime and hydrochemical characteristics can affect the removal rates of individual pesticides

Pituitary adenylate cyclase activating peptide (PACAP) participates in adipogenesis by activating ERK signaling pathway.

Pituitary adenylate cyclase activating peptide (PACAP) belongs to the secretin/glucagon/vasoactive intestinal peptide (VIP) family. Its action can be mediated by three different receptor subtypes: PAC1, which has exclusive affinity for PACAP, and VPAC1 and VPAC2 which have equal affinity for PACAP and VIP. We showed that all three receptors are expressed in 3T3-L1 cells throughout their differentiation into adipocytes. We established the activity of these receptors by cAMP accumulation upon induction by PACAP. Together with insulin and dexamethasone, PACAP induced adipogenesis in 3T3-L1 cell line. PACAP increased cAMP production within 15 min upon stimulation and targeted the expression and phosphorylation of MAPK (ERK1/2), strengthened by the ERK1/2 phosphorylation being partially or completely abolished by different combinations of PACAP receptors antagonists. We therefore speculate that ERK1/2 activation is crucial for the activation of CCAAT/enhancer- binding protein β (C/EBPβ)

Hip fractures and characteristics of living area : a fine-scale spatial analysis in France

Summary: We investigated the association between hip fracture incidence and living area characteristics in France. The spatial distribution of hip fractures incidence was heterogeneous and there was a significant relationship between social deprivation, urbanization, health access and hip fractures risk.Purpose: Several studies have shown great disparities in spatial repartition of hip fractures (HF). The aim of the study was to analyze the association between HF incidence and characteristics of the living area. Methods: All patients aged 50 or older, living in France, who were hospitalized for HF between 2012 and 2014 were included, using the French national hospital discharge database. Standardized Incidence Ratio (SIR) were calculated for each spatial unit and adjusted on age and sex. An ecological regression was performed to analyze the association between HF standardized incidence and ecological variables. We adjusted the model for neighborhood spatial structure. We used three variables to characterize the living areas: a deprivation index (French-EDI); healthcare access (French standardized index); land use (percentage of artificialized surfaces). Results: 236,328 HF were recorded in the French hospital national database, leading to an annual HF incidence of 333/100,000. The spatial analysis revealed geographical variations of HF incidence with SIR varying from 0.67 [0.52; 0.85] to 1.45 [1.23; 1.70]. There was a significant association between HF incidence rates and: (1) French-EDI index (trend p=0.0023); (2) general practitioner and nurse accessibility (trend p=0.0232 and p=0.0129, respectively); (3) percentage of artificialized surfaces (p<0.0001).Conclusion: the characteristics of the living area are associated with significant differences in the risk of hip fracture of older people.Résumé : Nous avons étudié l'association entre l'incidence des fractures de la hanche et les caractéristiques du lieu de vie en France. La répartition spatiale de l'incidence des fractures de la hanche était hétérogène et il existait une relation significative entre la privation sociale, l'urbanisation, l'accès à la santé et le risque de fracture de la hanche.Objectif : Plusieurs études ont montré de grandes disparités dans la répartition spatiale des fractures de hanche (FH). L'objectif de l'étude était d'analyser l'association entre l'incidence des FH et les caractéristiques du lieu de vie. Méthodes : Tous les patients âgés de 50 ans ou plus, résidant en France, qui ont été hospitalisés pour une HF entre 2012 et 2014 ont été inclus, en utilisant la base de données nationale française des sorties d'hôpital. Les ratios d'incidence standardisés (SIR) ont été calculés pour chaque unité spatiale et ajustés sur l'âge et le sexe. Une régression écologique a été réalisée pour analyser l'association entre l'incidence standardisée de l'HF et les variables écologiques. Nous avons ajusté le modèle pour la structure spatiale du quartier. Nous avons utilisé trois variables pour caractériser les zones de vie : un indice de privation (French-EDI) ; l'accès aux soins (indice standardisé français) ; l'utilisation du sol (pourcentage de surfaces artificialisées). Résultats : 236 328 HF ont été enregistrées dans la base de données nationale des hôpitaux français, conduisant à une incidence annuelle d'HF de 333/100 000. L'analyse spatiale a révélé des variations géographiques de l'incidence de l'HF avec un SIR variant de 0,67 [0,52 ; 0,85] à 1,45 [1,23 ; 1,70]. Il y avait une association significative entre les taux d'incidence de l'HF et : (1) l'indice French-EDI (tendance p=0,0023) ; (2) l'accessibilité des médecins généralistes et des infirmières (tendance p=0,0232 et p=0,0129, respectivement) ; (3) le pourcentage de surfaces artificialisées (p<0,0001).Conclusion : les caractéristiques du lieu de vie sont associées à des différences significatives dans le risque de fracture de hanche des personnes âgées

Late Holocene records from the Loire River incised paleovalley (French inner continental shelf): insights into regional and global forcing factors.

International audienc

Bacterial Communities characterization in coastal sedimentary infilling under fluids seeps influence using metagenomics (Concarneau and Croisic bays)

International audienc

Pesticide risk mitigation by vegetated treatment systems: a meta-analysis.

International audiencePesticides entering agricultural surface waters threaten water quality and aquatic communities. Recently, vegetated treatment systems (VTSs) (e.g., constructed wetlands and vegetated ditches) have been proposed as pesticide risk mitigation measures. However, little is known about the effectiveness of VTSs in controlling nonpoint source pesticide pollution and factors relevant for pesticide retention within these systems. Here, we conducted a meta-analysis on pesticide mitigation by VTSs using data from the scientific literature and the European LIFE ArtWET project. Overall, VTSs effectively reduced pesticide exposure levels (i.e., the majority of pesticide retention performances was >70%). A multiple linear regression analysis of 188 retention performance cases identified the two pesticide properties, organic carbon sorption coefficient value and water-phase 50% dissipation time, as well as the VTS characteristics overall plant coverage and hydraulic retention time for targeting high efficacy of pesticide retention. The application of a Tier I risk assessment (EU Uniform Principle) revealed a higher toxicity reduction for hydrophobic and nonpersistent insecticides compared with less sorptive and not readily degradable herbicides and fungicides. Overall, nearly half (48.5%) of all pesticide field concentrations ( = 130) failed Tier I standard risk assessment at the inlet of VTSs, and 29.2% of all outlet concentrations exceeded conservative acute threshold levels. We conclude that VTSs are a suitable and effective risk mitigation strategy for agricultural nonpoint source pesticide pollution of surface waters. Further research is needed to improve their overall efficacy in retaining pesticides

Sox8 and Sox9 act redundantly for ovarian-to-testicular fate reprogramming in the absence of R-spondin1 in mouse sex reversals

International audienceIn mammals, testicular differentiation is initiated by transcription factors SRY and SOX9 in XY gonads, and ovarian differentiation involves R-spondin1 (RSPO1) mediated activation of WNT/b-catenin signaling in XX gonads. Accordingly, the absence of RSPO1/Rspo1 in XX humans and mice leads to testicular differentiation and female-to-male sex reversal in a manner that does not requireSry or Sox9 in mice. Here we show that an alternate testis-differentiating factor exists and that this factor is Sox8. Specifically, genetic ablation of Sox8 and Sox9 prevents ovarian-to-testicular reprogramming observed in XX Rspo1 loss-of-function mice. Consequently, Rspo1 Sox8 Sox9 triple mutant gonads developed as atrophied ovaries. Thus, SOX8 alone can compensate for the loss of SOX9 for Sertoli cell differentiation during female-to-male sex reversal