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Water
No full textWater is a very vast topic, encompassing all periods and places of Antiquity. Many techniques and conceptions did not originate in the classical Greco-Roman world, but take their roots in the ancient Near East, Pharaonic Egypt and Bronze Age Greece which have been included in the discussion. Some uses of the resource have changed radically over the centuries, others not. Very different management practices, either rudimentary or more advanced, were employed contemporaneously across places. Rather than focusing on changes over time, this article therefore breaks down the subject into broad sub-sections and takes a synchronic ap-proach of Antiquity. After a few introductory remarks on ancient conceptions of water, it covers the key themes of water supply and uses, hydropower, rituals and risks. Given the breadth of the subject, some issues have been deliberately left out, such as water for survival in everyday life, cleaning and cooking, use in agriculture and livestock, health, medicine, and sanitation. These themes are not only addressed through textual evidence, but also through the results of decades of archaeological investigations. The integration of both aspects is indeed indispensable to form a global view of the matter and is now and became one of the most common approaches in this field of research
From movements to words: action monitoring in the medial frontal cortex along a caudal to rostral prediction error gradient
No full textSpeech error monitoring recruits the medial frontal cortex (MFC) region in the human brain. Error monitoring-related activity in the MFC has been interpreted both in terms of conflict monitoring and feedback-driven control, but as similar regions of the MFC are implicated in various levels of behavioral control ranging from basic motor movement control to high-level cognitive control functions, a more comprehensive account is needed. Moreover, as speech errors and other actions that involve varying control demands engage a widespread yet partially overlapping set of regions of the MFC, such an account should ideally explain the anatomical distribution of error-related functional activations within the MFC. Here we wanted to assess the hypothesis that the MFC has a similar role in the evaluation of action outcomes for motor and mental actions, operating along a rostral-caudal gradient of higher-lower level control demands involving prediction errors from both sensory and epistemic sources. To this end, we conducted an individual-specific annotation of task-fMRI BOLD activation peaks related to speech errors versus correct productions (i.e. that involve the largest cognitive control demands, Study I and II), tongue movement monitoring (i.e. that involve an intermediate level of cognitive and motor control demands) and tongue movement (i.e. that involve only motor control demands, Study II) in the MFC region. Results revealed overlapping clusters across the three contrasts across the MFC, but importantly both the number of peaks and their relative position along the rostral caudal axis were consistent with a hierarchical rostral caudal processing gradient in the MFC. While tongue movement showed more caudal activation in the MFC, speech errors showed more rostral activation, and tongue movement monitoring patterned in between. Furthermore, the combined results of both studies suggested that activation peaks were located more dorsally for participants that had a paracingulate gyrus, replicating a previously documented effect for movement and further supporting a common functional role of the MFC across very distinct actions
From lake to bog: A 15 kyr record of interplay between landscape changes and mercury accumulation (Réserve Naturelle du Luitel, 1250 m a. s. l., western Alps)
No full textInternational audienceLakes and peatlands are valuable archives for reconstructing past environmental dynamics. Multiproxy studies strive to unravel the complexity of interactions between factors influencing the past evolution of landscapes, including ecosystem dynamics, geomorphological trajectories, palaeoclimatic variability and past human activities. This study presents a unique 15,000-year multiproxy record detailing the transition of an alpine landscape from a lacustrine environment to a peatland ecosystem. The combination of high-resolution pollen analysis, inorganic trace elements measurements, and organic matter (OM) characterization by FTIR-ATR enables the connection of vegetation dynamics over time with its role in regulating soil (in)organic matter fluxes, including elements such as mercury (Hg). The results indicate that wet and warm climate episodes, such as the mid Holocene climate optimum, significantly enhance mercury uptake by vegetation and lake primary producers. This process is followed by Hg accumulation in the lacustrine environment, closely associated with fresh organic matter. In contrast, during cold and arid climatic periods, such as the Late Glacial, Hg uptake decreases in both the catchment and lake ecosystems. This reduction, coupled with dilution by minerogenic inputs, leads to lower Hg accumulation in the lake. Throughout the Holocene, the lake gradually transitions into a peatland. From the early to mid-Holocene, Hg accumulation is driven by a combination of lacustrine biological pumping, foliar uptake, and atmospheric deposition. Around ca 4500 cal a BP, the disappearance of catchment contribution to the archive drastically changes the interpretation of the mercury signal, which becomes primarily driven by the uptake of atmospheric Hg by bog vegetation. Mercury accumulation is therefore mainly controlled by changes in Hg deposition or reemissions, lake and peat development and OM humification. Finally, during the Late Holocene, local forest ecosystems decline, as pasturelands develop in the area. The natural Hg signal is also partially obscured by the effects of regional mining activitie
The Redshift-Space Momentum Power Spectrum III: measuring the growth rate from the SDSSv survey using auto- and cross- power spectrum of the galaxy density and momentum fields
No full textInternational audienceThe large-scale structure of the Universe and its evolution over time contains an abundance of cosmological information. One way to unlock this is by measuring the density and momentum power spectrum from the positions and peculiar velocities of galaxies, and fitting the cosmological parameters from these power spectrum. In this paper, we will explore the cross power spectrum between the density and momentum fields of galaxies. We derive the estimator of the density-momentum cross power spectrum multipoles. The growth rate of the large-scale-structure, is measured from fitting the combined density monopole, momentum monopole and cross dipole power spectrum. The estimators and models of power spectrum as well as our fitting method have been tested using mock catalogues, and we find that they perform well in recovering the fiducial values of the cosmological parameters of the simulations, and we also find that the errors of the parameters can be largely reduced by including the cross-power spectrum in the fit. We measure the auto-density, auto-momentum and cross power spectrum using the Sloan Digital Sky Survey Data Release 14 peculiar velocity catalogue. The fit result of the growth rate is at effective redshift , and our measurement is consistent with the prediction of the Cold Dark Matter cosmological model assuming General Relativity
Mandrin. Des derniers néandertaliens aux premiers hommes modernes en France méditerranéenne
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GEOPOLITIQUE DES RELIGIONS/ UN NOUVEAU ROLE DU RELIGIEUX DANS LES RELATIONS INTERNATIONALES? éditions Le Cavalier Bleu - Réédition actualisée, 2025
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Arabidopsis hydathodes are sites of intense auxin metabolism and nutrient scavenging
No full textAbstract Hydathodes are small organs located on the leaf margins of all vascular plants. They release excess xylem sap through guttation when stomata are closed or when the humidity level is high. Many promoter analyses have suggested other hydathode functions in metabolite transport and auxin metabolism, but experimental demonstration is still lacking. Here, we compared the transcriptomic and metabolomic features of mature Arabidopsis hydathodes to the leaf blade. 1460 differentially-expressed genes were identified revealing that genes related to auxin metabolism, transport, stress, DNA, plant cell wall, RNA or wax were on average more expressed in hydathodes. On the other hand, genes involved in glucosinolate metabolism, sulfation pathway, metal handling or photosynthesis were downregulated in hydathodes. In hydathodes, there are an increased expression of auxin transcriptional regulators and biosynthetic genes, a lower expression of auxin transport genes and a differential expression of genes related to its vacuolar storage that is consistent with increased contents of free and conjugated auxin. We also found that ca. 78% of the total content of 52 xylem sap metabolites were removed from guttation fluid at the hydathode level. Using reverse genetics, we showed that the capture of nitrate and phosphate in the guttation fluid relies on the NRT2.1 and PHT1;4 transporters, respectively. Thus, hydathodes absorb a significant part of xylem sap nutrients, limiting the loss of valuable chemicals during guttation. Our transcriptomic and metabolomic analyses reveal an organ with its own transcriptomic and physiological identity and highlight hydathode biological processes that may impact the whole plant. One sentence summary Transcriptome and physiological analysis of mature and healthy hydathodes of Arabidopsis demonstrates that those organs are sites of intense auxin metabolism and nutrient scavengin
En finir avec l’Antiquité ? Postcolonialismes et controverses dans les études classiques
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Euclid preparation. Sensitivity to neutrino parameters
No full textInternational audienceThe Euclid mission of the European Space Agency will deliver weak gravitational lensing and galaxy clustering surveys that can be used to constrain the standard cosmological model and extensions thereof. We present forecasts from the combination of these surveys on the sensitivity to cosmological parameters including the summed neutrino mass and the effective number of relativistic species in the standard CDM scenario and in a scenario with dynamical dark energy (CDM). We compare the accuracy of different algorithms predicting the nonlinear matter power spectrum for such models. We then validate several pipelines for Fisher matrix and MCMC forecasts, using different theory codes, algorithms for numerical derivatives, and assumptions concerning the non-linear cut-off scale. The Euclid primary probes alone will reach a sensitivity of 56meV in the CDM+ model, whereas the combination with CMB data from Planck is expected to achieve 23meV and raise the evidence for a non-zero neutrino mass to at least the level. This can be pushed to a detection if future CMB data from LiteBIRD and CMB Stage-IV are included. In combination with Planck, Euclid will also deliver tight constraints on \Delta N_{\rm eff}< 0.144 (95%CL) in the CDM++ model, or \Delta N_{\rm eff}< 0.063 when future CMB data are included. When floating , we find that the sensitivity to remains stable, while that to degrades at most by a factor 2. This work illustrates the complementarity between the Euclid spectroscopic and imaging/photometric surveys and between Euclid and CMB constraints. Euclid will have a great potential for measuring the neutrino mass and excluding well-motivated scenarios with additional relativistic particles
Effect of tomato, tomato-derived products and lycopene on metabolic inflammation: from epidemiological data to molecular mechanisms
No full textInternational audienceThe goal of this narrative review is to summarise the current knowledge and limitations related to the anti-inflammatory effects of tomato, tomato-derived products and lycopene in the context of metabolic inflammation associated to cardiometabolic diseases. The potential of tomato and tomato-derived product supplementation is supported by animal and in vitro studies. In addition, intervention studies provide arguments in favour of a limitation of metabolic inflammation. This is also the case for observational studies depicting inverse association between plasma lycopene levels and inflammation. Nevertheless, current data of intervention studies are mixed concerning the anti-inflammatory effect of tomato and tomato-derived products and are not in favour of an anti-inflammatory effect of pure lycopene in humans. From epidemiological to mechanistic studies, this review aims to identify limitations of the current knowledge and gaps that remain to be filled to improve our comprehension in contrasted anti-inflammatory effects of tomato, tomato-derived products and pure lycopene