Inflammation modulates intercellular adhesion and mechanotransduction in human epidermis via ROCK2

Aberrant mechanotransduction and compromised epithelial barrier function are associated with numerous human pathologies including inflammatory skin disorders. However, the cytoskeletal mechanisms regulating inflammatory responses in the epidermis are not well understood. Here we addressed this question by inducing a psoriatic phenotype in human keratinocytes and reconstructed human epidermis using a cytokine stimulation model. We show that the inflammation upregulates the Rho-myosin II pathway and destabilizes adherens junctions (AJs) promoting YAP nuclear entry. The integrity of cell-cell adhesion but not the myosin II contractilityper seis the determinative factor for the YAP regulation in epidermal keratinocytes. The inflammation-induced disruption of AJs, increased paracellular permeability, and YAP nuclear translocation are regulated by ROCK2, independently from myosin II activation. Using a specific inhibitor KD025, we show that ROCK2 executes its effects via cytoskeletal and transcription-dependent mechanisms to shape the inflammatory response in the epidermis

{Lower bounds on the performance of the MAP equalizer with a priori over MIMO systems}

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{The Impact of a priori information on the MAP equalizer performance with M-PSK modulation}

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Climatic change impact and associated uncertainty on catchment hydrology: a case study on the Chiba catchment in Tunisia

Projected changes in climate and their possible impacts on river flow are of concern for sustainable management of the water resources in Tunisia. Most of the climate model (CM) projections available so far suggest a decrease in precipitation and increase in temperature over the country in the future (next 25 to 50 years). These changes are expected to alter the catchment flow regime with exacerbated threats on the available water resources, yet limited and scarce. Surprisingly, there are few studies that quantify the impacts of climatic change on the catchment hydrology in Tunisia. One possible reason could be related to the inherent uncertainty in CM projection. Therefore, we here present a modelling approach that combines an ensemble of 4 CM projection to force the Soil and Water Assessment Tool (SWAT) physically based hydrological model for assessing changes and uncertainty in the hydrology of the Chiba catchment (North-East Tunisia) related to climatic change. Results indicate that the catchment is likely to experience drier conditions in the horizon 2050s facing a reduction in monthly flow magnitude, soil moisture conditions and water availability which is likely to be more pronounced in the dry season than in the rainy season

Uncertainty propagation in hydrological modeling

Uncertainty in hydrological model prediction stems from different sources such as parameter uncertainty, errors of input data, model structure uncertainty, lack of knowledge about the physical characteristics of the watershed and uncertainty in discharge data used to calibrate the model. Portioning and quantifying all these uncertainty sources that affect models and predictions is a difficult and challenging task due to the possible correlation of model parameters, to the propagation and correlation of the errors, to the model complexity, etc. Parameter uncertainty is usually considered as the main source of the model prediction uncertainty while discharge data uncertainty is rarely taken into account when calibrating the model. In this work a new calibration technique of the SWAT model is developed to account explicitly for the uncertainty in discharge data caused by uncertainty in the rating curve. For a given discharge value, a probability distribution function of true discharge was estimated from the constructed uncertain rating curves. This method was applied in three automatic calibration techniques SUFI2, GLUE and ParaSol to calibrate the SWAT model in two Mediterranean watersheds (Vène and Pallas). The uncertainty prediction confidence interval (95PPU) of each of the applied techniques was more successful at bracketing the measured data when uncertainty in the rating curve is accounted for. Discharge uncertainty contributed to total model uncertainty by 8 to 27 % (with an average value of 13 %) for the Vène watershed and by 3 to 20% (with an average value of 9 %) which shows that uncertainty in discharge measurement is not a negligible uncertainty source and has to be considered in hydrological modeling for more accurate model prediction that can be used in decision making for developing sustainable water resource management strategies

Quantifying hydrological responses of small Mediterranean catchments under climate change projections

Catchment flow regimes alteration is likely to be a prominent consequence of climate change projections in the Mediterranean. Here we explore the potential effects of climatic change on the flow regime of the Thau and the Chiba catchments which are located in Southern France and Northeastern Tunisia, respectively. The Soil and Water Assessment Tool (SWAT) hydrological model is forced with projections from an ensemble of 4 climate model (CM) to assess changes and uncertainty in relevant hydrological indicators related towater balance, magnitude, frequency and timing of the flow between a reference (1971–2000) and future (2041–2071) periods. Results indicate that both catchments are likely to experience a decrease in precipitation and increase in temperature in the future. Consequently, runoff and soilwater content are projected to decrease whereas potential evapotranspiration is likely to increase in both catchments. Yet uncertain, the projected magnitudes of these changes are higher in thewet period than in the dry period. Analyses of extreme flowshowsimilar trend in both catchments, projecting a decrease in both high flow and lowflow magnitudes for various time durations. Further, significant increase in low flow frequency as a proxy for hydrological droughts is projected for both catchments but with higher uncertainty in the wet period than in the dry period. Although no changes in the average timing of maximum and minimum flow events for different flow durations are projected, substantial uncertainty remains in the hydrological projections. While the results in both catchments show consistent trend of change for most of the hydrologic indicators, the overall degree of alteration on the flow regime of the Chiba catchment is projected to be higher than that of the Thau catchment. The projected magnitudes of alteration aswell as their associated uncertainty vary depending on the catchment characteristics and flow seasonality

Parameter and rating curve uncertainty propagation analysis of the SWAT model for two small Mediterranean catchments

The SWAT model was tested to simulate the streamflow of two small Mediterranean catchments (the Vène and the Pallas) in southern France. Model calibration and prediction uncertainty were assessed simultaneously by using three different techniques (SUFI-2, GLUE and ParaSol). Initially, a sensitivity analysis was conducted using the LH-OAT method. Subsequent sensitive parameter calibration and SWAT prediction uncertainty were analysed by considering, firstly, deterministic discharge data (assuming no uncertainty in discharge data) and secondly, uncertainty in discharge data through the development of a methodology that accounts explicitly for error in the rating curve (the stage−discharge relationship). To efficiently compare the different uncertainty methods and the effect of the uncertainty of the rating curve on model prediction uncertainty, common criteria were set for the likelihood function, the threshold value and the number of simulations. The results show that model prediction uncertainty is not only case-study specific, but also depends on the selected uncertainty analysis technique. It was also found that the 95% model prediction uncertainty interval is wider and more successful at encompassing the observations when uncertainty in the discharge data is considered explicitly. The latter source of uncertainty adds additional uncertainty to the total model prediction uncertainty

Assessment of the SWAT model prediction uncertainty using the GLUE approach A case study of the Chiba catchment (Tunisia)

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