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Soil water drainage is the main source of groundwater recharge and river flow. It is therefore a key process for water resource management. In this study, we evaluate the soil hydrology and the soil water drainage, simulated by the interactions between soil–biosphere–atmosphere (ISBA) land surface model currently used for hydrological applications from the watershed scale to the global scale, where parameters are generally not calibrated. This evaluation is done using seven lysimeters from two long-term model approach sites measuring hourly water dynamics between 2009 and 2019 in northeastern France. These 2 m depth lysimeters are filled with different soil types and are either maintained as bare soil or covered with vegetation. Four closed-form equations describing soil water retention and hydraulic conductivity functions are tested, namely the commonly used equations from and , a combination of the soil water retention function with the unsaturated hydraulic conductivity function, and, for the very first time in a land surface model (LSM), a modified version of the equations, with a new hydraulic conductivity curve proposed by. The results indicate good performance by ISBA with the different closure equations in terms of soil volumetric water content and water mass. The drained flow at the bottom of the lysimeter is well simulated, using , while some weaknesses appear with due to the abrupt shape near the saturation of its hydraulic conductivity function. The mixed form or the new hydraulic conductivity function from allows the solving of this problem and even improves the simulation of the drainage dynamic, especially for intense drainage events. The study also highlights the importance of the vertical heterogeneity of the soil hydrodynamic parameters to correctly simulate the drainage dynamic, in addition to the primary influence of the parameters characterizing the shape of the soil water retention function. [ABSTRACT FROM AUTHOR]

Soil water drainage is the main source of groundwater recharge and river flow. It is therefore a key process for water resource management. In this study, we evaluate the soil hydrology and the soil water drainage, simulated by the Interaction-Soil-Biosphere-Atmosphere (ISBA) land surface model currently used for hydrological applications from the watershed scale to the global scale. This evaluation is done using seven lysimeters from two long term model approach sites measuring hourly water dynamics between 2009 and 2019 in northeastern France. These 2-meter depth lysimeters are filled with different soil types and are either maintained bare soil or covered with vegetation. Four closed-form equations describing soil water retention and hydraulic conductivity functions, are tested: the commonly used equations from Brooks and Corey (1966) and van Genuchten (1980), a combination of the van Genuchten soil water retention function with the Brooks and Corey unsaturated hydraulic conductivity function, and, for the very first time in a Land Surface Model (LSM), a modified version of Van Genuchten equations, with a new hydraulic conductivity curve proposed by Iden et al. (2015). The results indicate a good performance by ISBA with the different closure equations in terms of soil volumetric water content and water mass. The drained flow at the bottom of the lysimeter is well simulated using Brooks and Corey (1966) while some weaknesses appear with van Genuchten (1980) due to the abrupt shape near saturation of its hydraulic conductivity function. The mixed form or the new van Genuchten hydraulic conductivity function from Iden et al. (2015) allows solving this problem and even improves the simulation of the drainage dynamic, especially for intense drainage events. The study also highlights the importance of the vertical heterogeneity of the soil hydrodynamic parameters to correctly simulate the drainage dynamic, as well as the primary influence of the parameters characterizing the shape of the soil water retention function. [ABSTRACT FROM AUTHOR]

Background: The treatment of patients with headache represents an important part of a neurologist's activity. It requires sufficient training for neurology residents. In France, residents in neurology can complete this training by attending specialized consultations or by participating in a postgraduate training program called "Diplôme Inter‐Universitaire Migraine et Céphalées" (DIUMC). Objective: The objective of this cross‐sectional study was to investigate the French residents' knowledge in headache medicine and the impact of different types of training in headache medicine that are available in France. Methods: An anonymous survey was carried out among 548 French residents in neurology. Results: The questionnaires of 121 residents (22.1%) were analyzed. Among them, 54.5% (66/121) had no complementary training apart from the internship (Group 1), 21.5% (26/121) had attended only specialized consultations (Group 2), and 24% (29/121) had participated in the DIUMC (Group 3). There was no difference between all groups regarding the knowledge of the prevalence of primary or chronic headaches. There was almost no difference between the groups in the management of episodic migraine. In contrast, the management of tension‐type headache and chronic headache was better known by residents of Group 3 than residents of Group 1. In these two diseases, residents of Group 3 offered prophylactic treatment more often. Almost 29% of the residents (35/121) had read the French guidelines for the diagnosis and management of migraine. In Group 3, residents had read them significantly more often (1.6% in Group 1, 38.5% in Group 2 and 62.1% in Group 3, p < 0.001). Conclusion: This study shows the lack of knowledge among French neurology residents regarding headache medicine. It highlights the interest of specific training programs that could improve the practical and theoretical knowledge of future neurologists. [ABSTRACT FROM AUTHOR]

Organic matter has an important role in biogeochemistry in aquatic environments. This study investigated impact of suspended particulate organic matter (SPOM) on fluorescence signal of mixtures of three water types (river water RW, sea water SW, effluent wastewater WW) using fluorescence (excitation-emission matrix, EEM) spectroscopy and parallel factor analysis (PARAFAC) and multilinear regression. Four irradiation experiments (Expt-1, Expt-2, Expt-3, and Expt-4) were conducted during different times of the year (two in autumn, one in winter, and one in spring season). Samples were exposed to natural sunlight on laboratory rooftop in University of Toulon, France, with another set of samples kept in dark as control samples. Three component (C1, C2, C3) model was validated by split-half and Concordia from the whole EEM dataset of all irradiation experiments. No protein-like fluorophores was found. The study revealed the effect of SPOM presence/absence on fluorescence signal of DOM and on resulting parameters of multilinear regression MLR model and kinetic constant of these MLR parameters. Kinetic constant (k) for all MLR coefficients was in order of greatness as Expt-1 (SPOM of WW only in mixtures) > Expt-3 (SPOM of SW only in mixtures) > Expt-2 (SPOM of RW only in mixtures)> Expt-4 (SPOM of RW + SW + WW in mixtures) indicating that SPOM of WW is the most resistant to photodegradation. For dark control samples, only relative standard deviation RSD could be calculated from dataset. RSD values for C3 were the highest indicating its chaotic variations, and the lowest RSD values were found for both C1 and C2 for all experiments. Statistical differences has been found between control and irradiated experiments. These models developed in this study can be used to predict fluorescence signal of anthropogenic effluent DOM during its transport in river systems to coastal zone. [ABSTRACT FROM AUTHOR]

Due to its short-lived progeny, including gaseous radon isotopes that can be inhaled and its significant transfer into vegetation, radium poses a substantial concern in radiation risk assessment. Although the transfer of Ra from soil to plants has been previously documented, the distribution and speciation of radium within the plant tissues, particularly within trees, remain unclear. The temporal dimension of Ra transfer is also poorly known. Therefore, the transfer of radium and others alkaline earth cations in beech trees was investigated through the analysis of fine (<2 mm) roots and leaves corresponding to tree organs with a life cycle limited to one season. This study was conducted at the experimental Montiers (INRAE-Andra site, France) and Strengbach watershed (OHGE site, France) beech-forested site. The activity of 226Ra and the isotopic ratio (228Ra/226Ra) were measured in roots and leaves using gamma spectrometry. Additionally, the concentration of alkaline earth cations (Mg, Ca, Sr, and Ba) was measured, to better constraint the mechanism of alkaline earth cation transfer through the xylem. The retention of these cations within the trees increases with the mass of the element, following the order Mg < Ca < Sr ≈ Ba < Ra, i.e.: light alkaline earth cations are more efficiently transferred from roots to leaves than heavy one. Our results suggest that these cations maintain their hydration shell during their ascent in stems and a low pH ion-exchange process rather than a complexation process with carboxylic group occurs. The decay of the (228Ra/226Ra) isotopic ratio over time during transfer within the trees allows us to quantify the slow Ra translocation from roots to the leaves, ranging from 1 to more than 16 years. This duration increases with the age of the trees. Hence, radioactive decay of Ra provides particularly valuable timescale information that is usually difficult to assess for Ca or other alkaline earth cations. [Display omitted] • Light alkaline earth cations are more transferred to leaves than heavy one. • Alkaline earth cations keep their hydration shell during ascent in tree stems. • The 228Ra/226Ra ratio provides a means to determine AE cations transfer time in trees. • The translocation of Ra in trees is really slow. • The residence time of Ra increases with the age and/or the size of the tree. [ABSTRACT FROM AUTHOR]