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Antibiotics have played a critical role in sustaining and improving livestock production in the past decades, but the emergence of antimicrobial resistance has led several countries to ban or limit their use. Since then, in-feed alternatives have gained a lot of attention but the development of efficacious alternatives implies a better understanding of the mode of action of antibiotic growth promoters (AGP) when administered at subtherapeutic concentrations. In the present study, 120 broiler chickens per group (8 pens/group) were fed for 35 d with either basal feed (control group) or feed supplemented with avilamycin (AGP group; 10 g/1,000 kg of feed). At the end of the trial, the ileum from the small intestine of 5 birds per group was sampled, and RNA were isolated for profiling their transcriptome via RNA sequencing (RNA-Seq). As expected, the growth of chickens in the AGP group was significantly higher than in the control group. Overall, 66 differentially expressed genes (false discovery rate ≤ 0.05 and fold change ≥ 2 or ≤ -2) were found in the ileum of chickens fed avilamycin in comparison with the control group. The functional analysis showed reduced activity of genes related to signaling by interleukins, with IL-22, SOCS3, and certain antimicrobial peptides found multiple times in these pathways in the AGP group at day 35. In addition, higher activity was predicted in a module of genes related to lipid metabolism and transport in the avilamycin group. The use of RNA-Seq allowed a snapshot of the whole transcriptome at day 35 and aimed at delivering additional data on the host-centric hypothesis regarding the mode of action of AGP (i.e. immunomodulation, reduction of the immunological stress)., (Copyright © 2020. Published by Elsevier Inc.)

Objectives: The purpose of this study was to describe and compare the initial management, including clinical/biological investigation and treatment, of new-onset seizures and status epilepticus (SE) in children versus seizures and SE in those with known epilepsy., Methods: This was a retrospective, single-center, observational study conducted in an urban pediatric hospital in Paris. All patients, aged from 1 month to 18 years, admitted to the pediatric intensive care unit, the high-dependency care unit, and those who required hospitalization in the short-term unit of the emergency department between January 1 and December 31, 2014 for seizures and/or SE were included., Results: We analyzed the data of 190 children: new-onset seizures (N=118; group A) versus those with known epilepsy (N=72; group B). At least one diagnostic test was performed on 156 patients (82.1%) (group A, N=104, 88.1%; group B, N=52, 72.2%; P=0.05). In group B, blood levels of antiepileptic drugs were measured in 14 of the 38 patients with SE, of whom six were under dosed. Treatments were: first line, diazepam (group A, 80%; group B, 46%; P<0.001); second line, diazepam (group A, 56%; group B, 34%; P=0.02) or clonazepam (group A, 24%; group B, 46%; P=0.001); third line, phenytoin (group A, 54%; group B, 22%; P<0.001) or clonazepam (group A, 18%; group B, 61%; P<0.001)., Conclusion: Diagnostic evaluation and treatment should be individualized for children with known epilepsy., (Copyright © 2019. Published by Elsevier Masson SAS.)

Understanding and predicting the propagation, deposition and resuspension of suspended particulate matter (SPM) in river networks is important for managing water resources, ecological habitat, pollution, navigation, hydropower generation, reservoir sedimentation, etc. Observational data are scarce and costly, and there is little feedback on the efficiency of numerical simulation tools for compensating the lack of data on a river scale of several hundreds of kilometers. This paper aims at exploring the use of a one-dimensional (1-D) hydrodynamical model for understanding the source and fate of SPM during complex events. The numerical model was applied to the May-June 2008 flood in the Lower Rhône River, France. This event was a combination of floods of the Isère (including dam flushing operations in the Lower Isère River) and Durance tributaries over a two-week period. The simulation code was used to model the SPM fluxes at a high spatial and temporal resolution using a multi-class approach. Approximately half of the 4.9 Mt of SPM measured at the outlet at Beaucaire were found to come from the Isère River and the other half from the Durance River, whereas previous studies estimated that most of the SPM flux at the outlet came from the Durance River. The amount of SPM trapped within the river network, mainly behind the first hydropower structure downstream of the Isère confluence, was estimated to be 3.7 Mt due to the deposition of the coarsest particles. Such a model proved to be able to compute the interaction of various grain size classes with dams and other structures. In turn, the quality of the results of SPM fluxes and deposition is highly sensitive to particle parameters, especially grain size distribution, and to the operational rules of reservoirs., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Long term and high resolution data on water discharge, suspended particulate matter (SPM) and contaminant concentrations in rivers are required for a better understanding of particulate transfers from the continental areas to the seas. The aim of this study was to provide a novel estimation of annual fluxes of SPM and related pollutants in the Rhône River from Lake Geneva to the Mediterranean Sea by combining high frequency or time-integrative monitoring and novel relations between SPM concentration (Cs) and water discharge (Q). At six stations of the Rhône Sediment Observatory (OSR), SPM fluxes were calculated over the 2000-2016 period by combining observational data and Cs-Q relations. Monthly average concentrations of mercury (Hg) and PCB 180 were obtained by analysis of SPM samples collected in time integrative particle traps between 2011 and 2016. These pollutants were selected because of the well documented contamination of the Rhône watershed by these substances. Inter-annual fluxes at the Rhône River outlet averaged 6.6 Mt. yr -1 for SPM, 572 kg yr -1 for Hg and 14 kg yr -1 for PCB 180. The Isère and Durance tributaries were found to be the main contributors of SPM fluxes. Annual SPM budgets were not balanced, suggesting deposition, remobilization of bottom sediments and/or contributions from non-monitored tributaries. The SPM sampled at the outlet was more contaminated than the combined SPM inputs from the monitored tributaries, suggesting that intermediate sources of contamination were not captured in the budget., (Copyright © 2018 Elsevier B.V. All rights reserved.)

A multi-technique approach is proposed to study sand dynamics in an engineered piedmont river. Only a few studies focused on such systems and innovative methodological protocols still need to be designed to better understand sand transport in piedmont rivers where bedload dynamics has been largely modified with nowadays a residual sand transport on a fixed gravel matrix. The proposed methodology is based on an analysis of bathymetry and turbidity measurements and on modelling, including the development of sediment rating curves and 2D numerical modelling, and using sediment budgeting for cross-validation. Its application to the Isère-Rhône confluence (France) provided some insights of sand fluxes in this complex river system where few sediment flux data are available. Indeed, a substantial amount of sand sporadically reaches the downstream part of the Isère River because of the presence of a series of dams, and jeopardizes navigation and flood management at the confluence. Based on the analysis of the 2015 flushing event, it was found that the sediment transport capacity was reached during the event whereas sand supply can be considered as null when dam bottom gates are closed. Suspended load of sand was prevailing downstream of the last dam but quickly settled down at the confluence. The sand deposit was eventually evacuated from the confluence during the small floods occurring after the flushing event with a minimum discharge of approximately 500 m 3 /s in the Isère River and 1000 m 3 /s in the headrace canal of the Rhône River. The presented methodology can be transferred to other sites with similar issues., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Weirs or run-of-river dams can disrupt bedload transfer with negative ecological effects downstream due to sediment starvation. The way and the degree to which bedload is trapped is nevertheless not straightforward and few studies have examined this topic. This study focuses on a 13-km-long reservoir of the Rhône River, France, created by a diversion dam equipped with bottom gates. Our main objective was to determine the degree of alteration of the bedload transfer downstream and to identify to which extent the implementation of Ecomorphogenic Flows (EmF), defined as environmental flows whose objective is specifically to increase bedload transfer through the reservoir to promote downstream habitat diversity, could increase bed mobility. The results show that the potential for morphological adjustments in the reservoir was already low before dam completion (1968) in response to a substantial decrease in coarse sediment supply, but that this potential was progressively reduced due to the impoundment. However, the bedload transfer continuity has been at least partially maintained since dam completion. According to numerical simulations, only particles smaller than medium gravels (d < 14 mm) could be exported downstream of the dam for relatively rare discharge (50-years return-interval flood). Implementation of EmF could neatly improve the bedload transfer since it would allow to strongly increase the competence: for a 2-years and a 50-years return-interval floods, the maximum particle size exportable downstream is respectively 9 and 4 times larger than for normal the reservoir operation., (Copyright © 2018. Published by Elsevier B.V.)

Monitoring hydrophobic contaminants in surface freshwaters requires measuring contaminant concentrations in the particulate fraction (sediment or suspended particulate matter, SPM) of the water column. Particle traps (PTs) have been recently developed to sample SPM as cost-efficient, easy to operate and time-integrative tools. But the representativeness of SPM collected with PTs is not fully understood, notably in terms of grain size distribution and particulate organic carbon (POC) content, which could both skew particulate contaminant concentrations. The aim of this study was to evaluate the representativeness of SPM characteristics (i.e. grain size distribution and POC content) and associated contaminants (i.e. polychlorinated biphenyls, PCBs; mercury, Hg) in samples collected in a large river using PTs for differing hydrological conditions. Samples collected using PTs (n = 74) were compared with samples collected during the same time period by continuous flow centrifugation (CFC). The grain size distribution of PT samples shifted with increasing water discharge: the proportion of very fine silts (2-6 μm) decreased while that of coarse silts (27-74 μm) increased. Regardless of water discharge, POC contents were different likely due to integration by PT of high POC-content phytoplankton blooms or low POC-content flood events. Differences in PCBs and Hg concentrations were usually within the range of analytical uncertainties and could not be related to grain size or POC content shifts. Occasional Hg-enriched inputs may have led to higher Hg concentrations in a few PT samples (n = 4) which highlights the time-integrative capacity of the PTs. The differences of annual Hg and PCB fluxes calculated either from PT samples or CFC samples were generally below 20%. Despite some inherent limitations (e.g. grain size distribution bias), our findings suggest that PT sampling is a valuable technique to assess reliable spatial and temporal trends of particulate contaminants such as PCBs and Hg within a river monitoring network., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Context: Very few studies have evaluated the role of procalcitonin (PCT) in infants with bronchiolitis., Aims: To describe infants who had both a diagnosis of bronchiolitis at the emergency department and a blood test including PCT, and to compare the characteristics of children according to the PCT value., Methods: Infants admitted to the Pediatric Emergency Department between 1 January 2014 and 31 December 2014 who had a diagnosis of bronchiolitis and a blood test including PCT were included. The clinical, biological, and radiological characteristics of the infants with PCT <1 or ≥1g/L were compared., Results: One hundred thirty six infants were included. Patients with high PCT (n=20) had a higher temperature (38.5°C, IQR=37.8-38.6 vs. 37.5°C, IQR=37.1-38.2; P<0.01), C-reactive protein (50mg/L, IQR=25-83 vs. 5mg/L, IQR=0-19; P<0.01), and neutrophils (7.8×10 9 /L, IQR=6.0-8.5 vs 4.5×10 9 /L, IQR=2.9-6.6; P<0.01) higher than patients with low PCT (n=116). Presence on the chest x-ray of alveolar condensation did not differ between the two PCT groups. Infants coming from the low-PCT group received fewer antibiotics (14.7% vs 65%; P<0.01)., Conclusion: In a Pediatric Emergency Department, PCT with a value of 1 or more cannot predict the presence of alveolar condensation on the chest x-ray. It seems to be associated with the antibiotics prescription, even if this could not be proved because of the design of the study., (Copyright © 2017. Published by Elsevier SAS.)

Changes in sperm features during the movement phase are especially interesting to study in external fertilization species whose sperm duration movement is long because this implies a significant adaptation of moving cells to the external medium. This study describes the changes in tetraploid Pacific oyster sperm characteristics in relation to time post activation. Sperm individually collected on three tetraploid males were activated in seawater. Their features were analysed over a 24h period and compared to a sperm pool collected on three diploid males as a reference. The percentage of motile spermatozoa, the intracellular ATP content, and the fine structure of spermatozoa were studied in relation to time post activation. Furthermore, the fertilisation capacity of sperm individually collected on five diploid males was assessed after 1 and 24h post activation. A forward progressive movement was maintained for at least a 20h duration. Compared to diploid males, the percentage of motile spermatozoa was lower in tetraploid males. The intracellular ATP concentration was higher in spermatozoa from tetraploid males than in spermatozoa from diploid males. A decrease in ATP content was observed in the first 6h post activation and severe alterations were observed in sperm morphology after 24h. Then, a lower fertilisation capacity of sperm from diploid males was observed at the end of the movement phase. The cessation of Pacific oyster sperm motility was unlikely caused by ATP consumption as ATP concentration was still high at the end of sperm movement but rather caused by drastic changes in sperm morphology. Compared to sperm collected on diploid males, the lower quality of sperm from tetraploid males was emphasized by a shorter movement duration and deeper morphological alterations at the end of the movement phase.