Integrated hydrological modelling of a managed coastal Mediterranean wetland (Rhone delta, France): initial calibration

This paper presents a model of a heavily managed coastal Mediterranean wetland. The hydrosystem studied , called ``Ile de Camargue', is the central part of the Rhone river delta. It comprises flat agricultural drainage basins, marshes, and shallow brackish lagoons whose connection to the sea is managed. This hydrosystem is subject to strong natural hydrological variability due to the combination of a Mediterranean climate and the artificial hydrological regime imposed by flooded rice cultivation. To quantify the hydrological balance at different spatial and temporal scales, a simplified model is developed — including the basin and the lagoons — using a time step that enables the temporal dynamic to be reproduced that is adapted to data availability. This modelling task takes into account the functioning of the natural and anthropogenic components of the hydrosystem. A conceptual approach is used for modelling drainage from the catchment, using a GIS to estimate water input for rice irrigation. The lagoon system is modelled using a two-dimensional finite element hydrodynamic model. Simulated results from the hydrodynamic model run under various hydro-climatic forcing conditions (water level, wind speed and direction, sea connection) are used to calculate hydraulic exchanges between lagoon sub units considered as boxes. Finally, the HIC ('Hydrologie de l’Ile de Camargue') conceptual model is applied to simulate the water inputs and exchanges between the different units, together with the salt balance in the hydrosystem during a calibration period.</p> <p style='line-height: 20px;'><b>Keywords: </b>water management,conceptual hydrological model, hydrodynamic model, box model, GIS, Rhone delta, Camargue

Integrated hydrological modelling of a managed coastal Mediterranean wetland (Rhone delta, France): initial calibration

International audienceThis paper presents a model of a heavily managed coastal Mediterranean wetland. The hydrosystem studied , called ``Ile de Camargue", is the central part of the Rhone river delta. It comprises flat agricultural drainage basins, marshes, and shallow brackish lagoons whose connection to the sea is managed. This hydrosystem is subject to strong natural hydrological variability due to the combination of a Mediterranean climate and the artificial hydrological regime imposed by flooded rice cultivation. To quantify the hydrological balance at different spatial and temporal scales, a simplified model is developed — including the basin and the lagoons — using a time step that enables the temporal dynamic to be reproduced that is adapted to data availability. This modelling task takes into account the functioning of the natural and anthropogenic components of the hydrosystem. A conceptual approach is used for modelling drainage from the catchment, using a GIS to estimate water input for rice irrigation. The lagoon system is modelled using a two-dimensional finite element hydrodynamic model. Simulated results from the hydrodynamic model run under various hydro-climatic forcing conditions (water level, wind speed and direction, sea connection) are used to calculate hydraulic exchanges between lagoon sub units considered as boxes. Finally, the HIC ("Hydrologie de l'Ile de Camargue") conceptual model is applied to simulate the water inputs and exchanges between the different units, together with the salt balance in the hydrosystem during a calibration period. Keywords: water management,conceptual hydrological model, hydrodynamic model, box model, GIS, Rhone delta, Camargue

The practices of apartheid as a war crime: a critical analysis

The human suffering caused by the political ideology of apartheid in South Africa during the Apartheid era (1948-1994) prompted worldwide condemnation and a variety of diplomatic and legal responses. Amongst these responses was the attempt to have apartheid recognised both as a crime against humanity in the 1973 Apartheid Convention as well as a war crime in Article 85(4)(c) of Additional Protocol I. This article examines the origins, nature and current status of the practices of apartheid as a war crime and its possible application to the Israeli-Palestinian conflict

Determinants of the voltage dependence of G protein modulation within calcium channel β subunits

CaVβ subunits of voltage-gated calcium channels contain two conserved domains, a src-homology-3 (SH3) domain and a guanylate kinase-like (GK) domain with an intervening HOOK domain. We have shown in a previous study that, although Gβγ-mediated inhibitory modulation of CaV2.2 channels did not require the interaction of a CaVβ subunit with the CaVα1 subunit, when such interaction was prevented by a mutation in the α1 subunit, G protein modulation could not be removed by a large depolarization and showed voltage-independent properties (Leroy et al., J Neurosci 25:6984–6996, 2005). In this study, we have investigated the ability of mutant and truncated CaVβ subunits to support voltage-dependent G protein modulation in order to determine the minimal domain of the CaVβ subunit that is required for this process. We have coexpressed the CaVβ subunit constructs with CaV2.2 and α2δ-2, studied modulation by the activation of the dopamine D2 receptor, and also examined basal tonic modulation. Our main finding is that the CaVβ subunit GK domains, from either β1b or β2, are sufficient to restore voltage dependence to G protein modulation. We also found that the removal of the variable HOOK region from β2a promotes tonic voltage-dependent G protein modulation. We propose that the absence of the HOOK region enhances Gβγ binding affinity, leading to greater tonic modulation by basal levels of Gβγ. This tonic modulation requires the presence of an SH3 domain, as tonic modulation is not supported by any of the CaVβ subunit GK domains alone

Live to cheat another day: bacterial dormancy facilitates the social exploitation of beta-lactamases

The breakdown of antibiotics by β-lactamases may be cooperative, since resistant cells can detoxify their environment and facilitate the growth of susceptible neighbours. However, previous studies of this phenomenon have used artificial bacterial vectors or engineered bacteria to increase the secretion of β-lactamases from cells. Here, we investigated whether a broad-spectrum β-lactamase gene carried by a naturally occurring plasmid (pCT) is cooperative under a range of conditions. In ordinary batch culture on solid media, there was little or no evidence that resistant bacteria could protect susceptible cells from ampicillin, although resistant colonies could locally detoxify this growth medium. However, when susceptible cells were inoculated at high densities, late-appearing phenotypically susceptible bacteria grew in the vicinity of resistant colonies. We infer that persisters, cells that have survived antibiotics by undergoing a period of dormancy, founded these satellite colonies. The number of persister colonies was positively correlated with the density of resistant colonies and increased as antibiotic concentrations decreased. We argue that detoxification can be cooperative under a limited range of conditions: if the toxins are bacteriostatic rather than bacteridical; or if susceptible cells invade communities after resistant bacteria; or if dormancy allows susceptible cells to avoid bactericides. Resistance and tolerance were previously thought to be independent solutions for surviving antibiotics. Here, we show that these are interacting strategies: the presence of bacteria adopting one solution can have substantial effects on the fitness of their neighbours

Tubulin Binds to the Cytoplasmic Loop of TRESK Background K+ Channel In Vitro.

The cytoplasmic loop between the second and third transmembrane segments is pivotal in the regulation of TRESK (TWIK-related spinal cord K+ channel, K2P18.1, KCNK18). Calcineurin binds to this region and activates the channel by dephosphorylation in response to the calcium signal. Phosphorylation-dependent anchorage of 14-3-3 adaptor protein also modulates TRESK at this location. In the present study, we identified molecular interacting partners of the intracellular loop. By an affinity chromatography approach using the cytoplasmic loop as bait, we have verified the specific association of calcineurin and 14-3-3 to the channel. In addition to these known interacting proteins, we observed substantial binding of tubulin to the intracellular loop. Successive truncation of the polypeptide and pull-down experiments from mouse brain cytosol narrowed down the region sufficient for the binding of tubulin to a 16 amino acid sequence: LVLGRLSYSIISNLDE. The first six residues of this sequence are similar to the previously reported tubulin-binding region of P2X2 purinergic receptor. The tubulin-binding site of TRESK is located close to the protein kinase A (PKA)-dependent 14-3-3-docking motif of the channel. We provide experimental evidence suggesting that 14-3-3 competes with tubulin for the binding to the cytoplasmic loop of TRESK. It is intriguing that the 16 amino acid tubulin-binding sequence includes the serines, which were previously shown to be phosphorylated by microtubule-affinity regulating kinases (MARK kinases) and contribute to channel inhibition. Although tubulin binds to TRESK in vitro, it remains to be established whether the two proteins also interact in the living cell

Queen mandibular pheromone: questions that remain to be resolved

The discovery of ‘queen substance’, and the subsequent identification and synthesis of keycomponents of queen mandibular pheromone, has been of significant importance to beekeepers and to thebeekeeping industry. Fifty years on, there is greater appreciation of the importance and complexity of queenpheromones, but many mysteries remain about the mechanisms through which pheromones operate. Thediscovery of sex pheromone communication in moths occurred within the same time period, but in this case,intense pressure to find better means of pest management resulted in a remarkable focusing of research activityon understanding pheromone detection mechanisms and the central processing of pheromone signals in themoth. We can benefit from this work and here, studies on moths are used to highlight some of the gaps in ourknowledge of pheromone communication in bees. A better understanding of pheromone communication inhoney bees promises improved strategies for the successful management of these extraordinary animals

From Antenna to Antenna: Lateral Shift of Olfactory Memory Recall by Honeybees

Honeybees, Apis mellifera, readily learn to associate odours with sugar rewards and we show here that recall of the olfactory memory, as demonstrated by the bee extending its proboscis when presented with the trained odour, involves first the right and then the left antenna. At 1–2 hour after training using both antennae, recall is possible mainly when the bee uses its right antenna but by 6 hours after training a lateral shift has occurred and the memory can now be recalled mainly when the left antenna is in use. Long-term memory one day after training is also accessed mainly via the left antenna. This time-dependent shift from right to left antenna is also seen as side biases in responding to odour presented to the bee's left or right side. Hence, not only are the cellular events of memory formation similar in bees and vertebrate species but also the lateralized networks involved may be similar. These findings therefore seem to call for remarkable parallel evolution and suggest that the proper functioning of memory formation in a bilateral animal, either vertebrate or invertebrate, requires lateralization of processing

A

Abstract:&nbsp; Human Bocavirus-1/HBoV1 causes acute respiratory infections/ARI (bronchiolitis/pneumonia) mostly in young children. It was identified in 2005 and has not yet been incorporated into the routine virus screening in ARI. Symptoms of viral pneumonia in children less than 2 years old are often interpreted as of bacterial etiology, leading to unnecessary administration of antibiotics. Objective: to report the case of a previously healthy infant who developed HBoV1 pneumonia without complications, in order to consider HBoV1 as one of the possible agents involved. Clinical case. 19-month-old female, full-term/2780 grams. No relevant personal or familiar pathological history; complete vaccination. Reason for consultation: fever, cough, and shortness of breath. Antecedents: 3 days before, she started with rhinitis and dry cough. She had a fever peak of 38.7°C, so her pediatrician prescribed oral amoxicillin. On Apr/26/2021 she went to the emergency service due to persistent fever and worsening cough. Mild/moderate respiratory distress was observed; inhaled adrenergic drugs were administered, with good clinical response and outpatient follow-up (prior swabbing for COVID-19). The next day, she returned with food rejection and was hospitalized. Laboratory: hemoglobin 10.9g/dl, hematocrit 34%; leukocytes: 15,380 (69/15/15); platelets 299,000/ml; gases: 7.48/27.2/84.2/19.9/-2.1); ionogram Na 134/K 4/Cl 100; CRP: 17.8. Chest X-ray compatible with viral pneumonia. O2 saturation: 93%. Amoxicillin was suspended; hydration, oxygen by nasal cannula (3 liters/min) and inhaled salbutamol were administered. The complete panel of respiratory viruses was negative (RSV, Parainfluenza 1-3, Metapneumovirus, Influenza A/B and Adenovirus by IF; PCR for COVID-19: negative). HBoV1 detected in nasal secretions and serum (PCR with high viral load/&gt;1x106 c.gen/mL) was the only positive finding. Evolution: 48 hours after admission she was afebrile; O2 saturation 95%; supplementary oxygen therapy was suspended. Patient was discharged without complications. In the follow-up (10 days) she did not show relapses or respiratory symptoms, so aerosol therapy was suspended. Conclusions. A case of HBoV1 infection in an infant with no comorbidity is reported. Recognition of the viral etiology in hospitalized cases of pneumonia contributes to optimize the clinical management of patients with rational use of antibiotics. HBoV1 should be included in the standard screening for respiratory infections in hospitalized infants.Resumen:&nbsp; Bocavirus humano-1/HBoV1 es un parvovirus que causa infecciones respiratorias/IRA (bronquiolitis o neumonía) sobre todo en niños pequeños. Fue identificado en 2005 y aún no está incorporado a la pesquisa de virus habituales en IRA. Los cuadros de neumonía viral en menores de 2 años suelen interpretarse como de etiología bacteriana, administrándoles antibióticos innecesariamente. Objetivo: Reportar el caso de una lactante, sin comorbilidades previas, que desarrolla neumonía por HBoV1 sin complicaciones, a fin de considerar a este virus como uno más de los posibles agentes involucrados. Caso clínico. Paciente femenina de 19 meses de edad, nacida a término/2780gramos. Sin antecedentes patológicos, ni familiares relevantes; vacunación completa. MC: fiebre, tos y dificultad respiratoria. Antecedentes: 3 días previos inicia con rinitis y tos seca. Presenta un pico febril de 38,7°C por lo que su pediatra prescribió amoxicilina vía oral. El día 26/04/2021 concurre al servicio de emergencia por persistencia de la fiebre y empeoramiento de la tos. Se objetiva dificultad respiratoria leve/moderada; se administra adrenérgicos inhalados, con buena repuesta clínica y seguimiento ambulatorio (previo hisopado para COVID-19). Al día siguiente, ante el rechazo alimentario se decide internación. Laboratorio: Hemoglobina 10.9g/dl-Hto 34%; GB:15.380(69/15/15); plaquetas 299.000/ml; Gases:7.48/27.2/84.2/19.9/-2.1); Ionograma (Na134/K4/Cl100); PCR:17.8. Rx tórax compatible con neumonía viral. SatO2:93%. Se suspende amoxicilina, se administra hidratación, oxígeno por naricera-3litros/min y salbutamol inhalado. El panel completo de virus respiratorios resultó negativo (IFI para VRS, Parainfluenza 1,2,3, Metapneumovirus, Infuenza A y B y Adenovirus; PCR para COVID-19: negativo). Detección de HBoV1 en secreciones nasales y suero (PCR positiva con alta carga viral/&gt;1x10^6c.gen/mL) fue el único hallazgo positivo. Evolución: a las 48 hs. del ingreso estaba afebril; Sat 95%; se suspende oxigenoterapia. Alta sin complicaciones. El seguimiento (hasta 10 días) no mostró recaídas o sintomatología respiratoria por lo que se suspende aerosolterapia. Conclusiones. Se reporta un caso de infección por BoVH1 en lactante sin comorbilidad previa. El reconocimiento de la etiología viral en los cuadros hospitalizados por neumonía contribuye a optimizar el manejo clínico de estos pacientes con uso más racional de antibióticos. La detección de BoVH1 debería ser parte de la pesquisa estándar para infecciones respiratorias en lactantes hospitalizados