Délégation Rhône Auvergne

Abstract The structural framework of soil mediates all soil processes, at all relevant scales. The spatio‐temporal heterogeneity prevalent in most soils underpins the majority of biological diversity in soil, providing refuge sites for prey against predator, flow paths for biota to move, or be moved, and localized pools of substrate for biota to multiply. Just as importantly, soil biota play a crucial role in mediating soil structure: bacteria and fungi aggregate and stabilize structure at small scales (μm–cm) and earthworms and termites stabilize and create larger‐scale structures (mm–m). The stability of this two‐way interaction of structure and biota relations is crucial to the sustainability of the ecosystem. Soil is constantly reacting to changes in microclimates, and many of the soil–plant–microbe processes rely on the functioning of subtle chemical and physical gradients. The effect of global change on soil structure–biota interactions may be significant, through alterations in precipitation, temperature events, or land‐use. Nonetheless, because of the complexity and the ubiquitous heterogeneity of these interactions, it is difficult to extrapolate from general qualitative predictions of the effects of perturbations to specific reactions. This paper reviews some of the main soil structure–biota interactions, particularly focusing on soil stability, and the role of biota mediating soil structures. The effect of alterations in climate and land‐use on these interactions is investigated. Several case studies of the effect of land‐use change are presented.

Abstract Urban alteration of neutral and adaptive evolutionary processes is still underexplored. Using a genome-wide SNP dataset, we investigated (i) urban-induced modifications of population demography, genetic diversity and population structure and (ii) signature of divergent selection between urban and forest populations in the ant species, Temnothorax nylanderi. Our results did not reveal an impact of urbanization on neutral processes since we observed: (i) analogous genetic diversity among paired urban/forest sites and two control populations; (ii) weak population genetic structure explained neither by habitat (urban versus forest) nor by geography; (iii) a remarkably similar demographic history across populations with an ancestral growth followed by a recent decline, regardless of their current habitat or geographical location. The micro-geographical home range of ants may explain their resilience to urbanization. Finally, we detected 19 candidate loci discriminating urban/forest populations and associated with core cellular components, molecular function or biological process. Two of these loci were associated with a gene ontology term that was previously found to belong to a module of co-expressed genes related to caste phenotype. These results call for transcriptomics analyses to identify genes associated with ant social traits and to infer their potential role in urban adaptation.

For many plant species, nutrient availability induces important anatomical responses, particularly the production of low-density tissues to the detriment of supporting tissues. Due to the contrasting biomechanical properties of plant tissues, these anatomical responses may induce important modifications in the biomechanical properties of plant organs. The aim of this study was to determine the effects of nutrient enrichment on the anatomical traits of two freshwater plant species and its consequences on plant biomechanical performance. Two plant species were grown under controlled conditions in low versus high nutrient levels. The anatomical and biomechanical traits of the plant stems were measured. Both species produced tissues with lower densities under nutrient-rich conditions, accompanied by modifications in the structure of the aerenchyma for one species. As expected, nutrient enrichment also led to important modifications in the biomechanical properties of the stem for both species. In particular, mechanical resistance (breaking force and strength) and stiffness of stems were significantly reduced under nutrient rich conditions. The production of weaker stem tissues as a result of nutrient enrichment may increase the risk of plants to mechanical failure, thus challenging plant maintenance in mechanically stressful or disturbed habitats.

The placental skull has evolved into myriad forms, from longirostrine whales to globular primates, and with a diverse array of appendages from antlers to tusks. This disparity has recently been studied from the perspective of the whole skull, but the skull is composed of numerous elements that have distinct developmental origins and varied functions. Here, we assess the evolution of the skull's major skeletal elements, decomposed into 17 individual regions. Using a high-dimensional morphometric approach for a dataset of 322 living and extinct eutherians (placental mammals and their stem relatives), we quantify patterns of variation and estimate phylogenetic, allometric and ecological signal across the skull. We further compare rates of evolution across ecological categories and ordinal-level clades and reconstruct rates of evolution along lineages and through time to assess whether developmental origin or function discriminate the evolutionary trajectories of individual cranial elements. Our results demonstrate distinct macroevolutionary patterns across cranial elements that reflect the ecological adaptations of major clades. Elements derived from neural crest show the fastest rates of evolution, but ecological signal is equally pronounced in bones derived from neural crest and paraxial mesoderm, suggesting that developmental origin may influence evolutionary tempo, but not capacity for specialisation. This article is part of the theme issue 'The mammalian skull: development, structure and function'.

Here, we review the literature on sexual lability in dioecious angiosperm species with well-studied sex chromosomes. We distinguish three types of departures from strict dioecy, concerning either a minority of flowers in some individuals (leakiness) or the entire individual, which can constantly be bisexual or change sex. We found that for only four of the 22 species studied, reports of lability are lacking. The occurrence of lability is only weakly related to sex chromosome characteristics (number of sex-linked genes, age of the non-recombining region). These results contradict the naive idea that lability is an indication of the absence or the recent evolution of sex chromosomes, and thereby contribute to a growing consensus that sex chromosomes do not necessarily fix sex determination once and for all. We discuss some implications of these findings for the evolution of sex chromosomes, and suggest that more species with well-characterized lability should be studied with genomic data and tools. This article is part of the theme issue 'Sex determination and sex chromosome evolution in land plants'.

Abstract The influence of the reaction conditions (time, temperature, concentrations of the monomer, and the initiator) on the amount and composition of the oligomers and high molecular products formed during the heterogeneous anionic polymerization of ϵ‐caprolactone was investigated. The polymerization was initiated by KC 24 in xylene or tetrahydrofuran. Conditions were found under which intra‐ and intermolecular transesterification was strongly suppressed, thus providing the opportunity for the formation of polyesters with viscometric molecular masses of more than 300,000 and good yields (80% and higher). The total quantity of products with a viscometric molecular mass below 2500 did not exceed 15%; that of the cyclic dimer was not in excess of 5%. Peculiar features of the KC 24 initiated polymerization are the insignificant rise in the number of oligomers and the formation of high polymers even in strongly diluted solutions of ϵ‐caprolactone (0.2 mol/L and lower). The quantity and molecular mass of the polymers obtained decreased as the temperature increased. It was also established that the polymerization of the cyclic dimer of ϵ‐caprolactone is not initiated by KC 24 .

<ns3:p> <ns3:bold>Background:</ns3:bold> Single-cell studies have demonstrated the presence of significant cell-to-cell heterogeneity in gene expression. Whether such heterogeneity is only a bystander or has a functional role in the cell differentiation process is still hotly debated. </ns3:p> <ns3:p> <ns3:bold>Methods:</ns3:bold> In this study, we quantified and followed single-cell transcriptional uncertainty – a measure of gene transcriptional stochasticity in single cells – in 10 cell differentiation systems of varying cell lineage progressions, from single to multi-branching trajectories, using the stochastic two-state gene transcription model. </ns3:p> <ns3:p> <ns3:bold>Results:</ns3:bold> By visualizing the transcriptional uncertainty as a landscape over a two-dimensional representation of the single-cell gene expression data, we observed universal features in the cell differentiation trajectories that include: (i) a peak in single-cell uncertainty during transition states, and in systems with bifurcating differentiation trajectories, each branching point represents a state of high transcriptional uncertainty; (ii) a positive correlation of transcriptional uncertainty with transcriptional burst size and frequency; (iii) an increase in RNA velocity preceding the increase in the cell transcriptional uncertainty. </ns3:p> <ns3:p> <ns3:bold>Conclusions:</ns3:bold> Our findings suggest a possible universal mechanism during the cell differentiation process, in which stem cells engage stochastic exploratory dynamics of gene expression at the start of the cell differentiation by increasing gene transcriptional bursts, and disengage such dynamics once cells have decided on a particular terminal cell identity. Notably, the peak of single-cell transcriptional uncertainty signifies the decision-making point in the cell differentiation process. </ns3:p>

The ongoing obesity epidemic is a consequence of a progressive energy imbalance. The energy-balance model (EBM) posits that obesity results from an excess in food intake and circulating fuels. A reversal in causality has been proposed recently in the form of the carbohydrate-insulin model (CIM), according to which fat storage drives energy imbalance. Under the CIM, dietary carbohydrates shift energy use in favour of storage in adipose tissue. The dynamics of lipid storage and mobilization could, therefore, be sensitive to changes in carbohydrate intake and represent a measurable component of the CIM. To characterize potential changes in lipid dynamics induced by carbohydrates, mathematical models were used. Here, we propose a coherent mathematical implementation of the CIM-energy deposition model (CIM-EDM), which includes lipid turnover dynamics. Using lipid turnover data previously obtained by radiocarbon dating, we build two cohorts of virtual patients and simulate lipid dynamics during ageing and weight loss. We identify clinically testable lipid dynamic parameters that discriminate between the CIM-EDM and an energy in, energy out implementation of the EBM (EBM-IOM). Using a clinically relevant two-month virtual trial, we additionally identify scenarios and propose mechanisms whereby individuals may respond differently to low-carbohydrate diets. This article is part of a discussion meeting issue 'Causes of obesity: theories, conjectures and evidence (Part II)'.

In the last two decades, multiple ICT evolutions boosted the ability to collect and analyze vast amounts of data (on the order of Zettabytes). Collectively, they paved the way for the so-called data economy, revolutionizing most sectors of our society, including healthcare, transportation, and grids. At the core of this revolution, distributed data-intensive applications compose services operated by multiple parties in the cloud-edge continuum; they process, manage and exchange massive amounts of data at an unprecedented rate. However, data hold little value without adequate data protection. Traditional solutions, which aim to balance data quality and protection, are insufficient to address the peculiarities of the data economy, including trustworthy data sharing and management, composite service support, and multi-party data life cycle. This article analyzes how trust management systems can regain the lead in supporting trustworthy data-intensive applications, discussing current challenges and proposing a roadmap for new-generation trust management systems in the data economy.

We prove a multivariable approximate Carleman theorem on the determination of complex measures on R n and R n + by their moments. This is achieved by means of a multivariable Denjoy-Carleman maximum principle for quasi-analytic functions of several variables. As an application, we obtain a discrete Phragmn-Lindelf-type theorem for analytic functions on C n + .

Several aspects of the management of post-thrombotic syndrome (PTS) are still a matter of debate, or not yet addressed in international guidelines. The objective of this expert consensus from the French Society of Vascular Medicine (SFMV) and the French Society of Cardiovascular Imaging (SFICV) was to define the main elements of diagnosis and treatment of this syndrome, and to develop a proposal for its preoperative, procedural and follow-up management. In this consensus, the following issues were addressed: clinical and ultrasound diagnosis; pre-procedural workup; indications and contraindications to venous recanalisation; procedures; clinical and duplex ultrasound reports; follow-up; long-term treatment; management of great saphenous vein incompetency; anticoagulant and antiplatelet therapy after venous stenting.

Influenza, respiratory syncytial virus (RSV) and SARS-CoV-2 are among the main respiratory viruses circulating in the population, with a significant burden on public health. While individuals at higher risk are more likely to develop severe symptoms leading to hospitalization, viral circulation in the community remains less extensively monitored. This study compared viral circulation between RELAB, a recently established community-based laboratory surveillance network (n = 22 843 tested patients) and hospital surveillance at the Hospices Civils de Lyon, France (n = 23 046 tested patients), for the season 2023-2024. For influenza and SARS-CoV-2, similar trends were observed in at-risk populations (children under 5 years and adults over 65 years) in both settings. Circulation of these two viruses was first detected in the community and insights from the young adult population (19-64 years) were only captured in the community network. Circulation of RSV was more intense in terms of number of cases and started in the pediatric population, and consequently was more represented in the hospital setting. In conclusion, this study highlighted the complementarity between community and hospital surveillance, as different populations and periods of viral circulation were observed.

Four deuterium‐labelled neoglycolipids derived from cholesterol were synthesized for embedment into liposomes. Deuterium atoms were either incorporated by CH 2 replacement with a CD 2 group in the triethylene glycol spacer arm between the cholesteryl residue and the sugar moiety (products 2–4 ) or incorporated directly on the acetamido function in the sugar head (compound 5 ).

Abstract Impact loads significantly affect lubrication and operating reliability in crucial engineering applications such as gears and rolling bearings. To address the shortage of pure impact investigations on finite-length line contacts, this paper exhibits a two-dimensional elastohydrodynamic lubrication (EHL) model of pure impact. Using the multigrid multiintegration method for elastic deformation analysis and the multigrid method for solving the transient Reynolds equation, the authors investigate the effects of impact velocity and initial impact gap on contact properties. The findings show that the effect of increasing the initial impact gap on pure impact EHL can be referenced to the effect of transitioning from starved lubrication to fully lubricated on rolling EHL. These insights provide some theoretical support for engineering applications.

This paper reviews the application of second harmonic generation (SHG) to characterize dielectric-semiconductor interfaces used in microelectronics and photovoltaics. Based on non-linear optics, the method is non-destructive, so particularly advantageous for thin films. The theoretical background shows the possibility to access the electric field at interfaces and consequently to have a non-destructive measurement for interface state densities or fixed charges in oxides. Two more detailed examples of application of SHG characterization will be shown: field-effect passivation of silicon using thin film deposited alumina and interface analysis of silicon-on-insulator substrates.

We offer a collection of videos showing simulations of pedestrian crowds made with the LEMONS software. LEMONS is an open-source computational tool designed for modelling dense crowds. The platform features an intuitive online interface, enabling users to generate 2D and 3D pedestrian crowds based on anthropometric data. Additionally, it features a C++ library that computes mechanical contacts with other agents and obstacles, and evolves the crowd's configuration. Both the online platform and the library can readily be called from Python scripts, providing users with complete flexibility to implement their own decision-making models, such as specifying the desired velocities of individuals within the crowd. Documentation is also provided.

This deposit contains the processed data (.bam files) for the preprint https://doi.org/10.1101/2023.05.27.542554Scripts to produce these files, as well as genome and annotations to explore this data in IGV are available at https://gitlab.inria.fr/erable/te_long_read.Raw fastq files are available at the BioProject PRJNA956863

The link between Australian and European polymer science has traditionally been a very strong one, ranging from the frequent interchange of post-doctoral researchers to joint PhDs programs between European and Australian universities (e.g. QUT/KIT) or even strategic research alliances (e.g. Monash/Warwick). The cross-continental research activities additionally include frequent conference attendances on both continents, for example at the last European Poly­mer Federation Congress in Dresden in June 2015, where a dedicated and highly successful Australian/European workshop was held to identify avenues to further strengthen the collaborative efforts. The 36th Australasian Polymer Symposium held in Lorne, Victoria, in November of this year will see substantial European involvement and the up-coming European Polymer Federation Conference in Lyon in 2017 will welcome a large Australian delegation in a dedicated workshop. In the current issue of Macro­molecular Chemistry and Physics, we have collated articles from European and Australian teams to showcase their science, demonstrate the diversity of the offered research themes and inspire the macromolecular communities on both continents to explore what European/Australian collaboration has to offer. Daniel Keddie and team explore the behavior of phosphine monomers via the arguably most Australian polymerisation method, i.e. the Reversible Addition Fragmentation Chain Transfer (RAFT) process, while James Blinco and colleagues have a closer look at the profluorescent properties of nitroxides and their applications. The efficient RAFT polymerisation of fluorine-containing monomers is assessed by Vincent Ladmiral and coworkers. Gaining information on the diffusive properties of macromolecules is an important exercise to assess their hydrodynamic volume in solution and Arnaud Favier and his team demonstrate how DOSY NMR can provide important solution para­meters of RAFT prepared polymers. Moving into the biological applications of macromolecules, Martina Stenzel investigates how the ratio of positive and negative charges on poly­mers influences their cellular up-take, guiding future polymeric drug design efforts, while Markus Müllner explores the use of brush nanoparticles for delivery and imaging applications. Staying in the realm of polymer-driven biomedical applications, Holger Schönherr, Nicolas Voelker and coworkers introduce a polymer based theranostic approach to detect bacterial infections, while Neil Cameron and team discuss how the movement of pesticides can be controlled by using polymeric drift control agents. The synthesis of star polymers prepared by RAFT polymerisation for theranostic applications is introduced by Andrew Whittaker and colleagues, while Nicolas Voelker and team explore new synthetic routes to glycerols. Steven Howdle and his team are showing how dispersion poly­merization in supercritical CO2 can be exploited for controlling the size and morphology of polymer particles. Finally, Abraham Chemtob moves into the area of photoinitiation of radical polymerisation processes, showing that surface based initiation strategies provide a potential avenue for reaction scale-up. These studies are excellent highlights of the breadth and quality of research undertaken on both continents, often based on strong collaborations between Australian and European teams. We hope this special issue will showcase the growing momentum of Australo-European interactions in the field of macro­molecular science. Stay connected and Happy Reading!

BACKGROUND: In the field of biomarker validation with mass spectrometry, controlling the technical variability is a critical issue. In selected reaction monitoring (SRM) measurements, this issue provides the opportunity of using variance component analysis to distinguish various sources of variability. However, in case of unbalanced data (unequal number of observations in all factor combinations), the classical methods cannot correctly estimate the various sources of variability, particularly in presence of interaction. The present paper proposes an extension of the variance component analysis to estimate the various components of the variance, including an interaction component in case of unbalanced data. RESULTS: We applied an experimental design that uses a serial dilution to generate known relative protein concentrations and estimated these concentrations by two processing algorithms, a classical and a more recent one. The extended method allowed estimating the variances explained by the dilution and the technical process by each algorithm in an experiment with 9 proteins: L-FABP, 14.3.3 sigma, Calgi, Def.A6, Villin, Calmo, I-FABP, Peroxi-5, and S100A14. Whereas, the recent algorithm gave a higher dilution variance and a lower technical variance than the classical one in two proteins with three peptides (L-FABP and Villin), there were no significant difference between the two algorithms on all proteins. CONCLUSIONS: The extension of the variance component analysis was able to estimate correctly the variance components of protein concentration measurement in case of unbalanced design.

BACKGROUND: The aim of this study was twofold: 1) to determine the rate of performance improvement among France's top 10 athletes in middle- and long-distance events (e.g., 800 m, 1500 m and 5000 m) by analyzing their personal best performances per season over several years; and 2) to develop an index of the optimal performance improvement rate for use by elite coaches and athletes in assessing athletes' progression, predicting potential performances, and possibly detecting high-potential athletes. METHODS: The top 10 athletes in the Fédération Française d'Athlétisme (FFA) rankings of the 800-m, 1500-m and 5000-m events for each sex were assessed for their history of race times before achieving their best race time (BRT). For each athlete, the difference between the current BRT and last season's BRT was defined as the 1-season improvement rate (1-SIR), whereas the average improvement rate in the last and preceding seasons was the multiseason improvement rate (M-SIR). RESULTS: Sex differences were observed in the 5000 m only for M-SIR (%) (P<0.05), and significantly higher rates of improvement were observed for 1-SIR (min) and M-SIR mostly for the 5000 m as opposed to the 800 m and 1500 m. CONCLUSIONS: Prediction using this index may be used to detect talents (those who have the potential for high level performances and/or the potential to break national records) and to follow and optimize training strategy and competitions.