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To assess appropriateness of end-of-life treatments provided to actively dying patients attending the emergency department of a primary care hospital.

RNA silencing processes use exogenous or endogenous RNA molecules to specifically and robustly regulate gene expression. In C. elegans, initial mechanistic descriptions of the different silencing processes focused on posttranscriptional regulation. In this review, we discuss recent work showing that, in this model organism, RNA silencing also controls the transcription of target genes by inducing heterochromatin formation. Specifically, it has been shown that ribonucleoprotein complexes containing small RNAs, either processed from exogenous dsRNA or synthesized from the genome itself, and proteins of the Argonaute family, mediate the deposition of repressive histone marks at the targeted loci. Interestingly, the accumulation of repressive marks is required for the inheritance of the silencing effect and the establishment of an epigenetic memory that discriminates self- from non-self-RNAs.

Based on high‐resolution laboratory data of instantaneous surface elevation and fluid velocity associated with the propagation of short waves over a gently sloping beach (GLOBEX project), the present work compares two methods for predicting the wave setup. A one‐dimensional (cross‐shore) model is considered to solve the balance equation that links the pressure gradient induced by the mean surface elevation profile with the wave radiation stress (including wave roller) and bottom stress profiles. When compared to measurements and using a wave‐by‐wave approach, the mean elevation appears to be significantly better predicted with a nonlinear approach based on stream function theory than with the commonly used linear approach based on Airy wave theory. At the shoreline, the linear method overestimates the wave setup by at least about 50%while this error is globally reduced by a factor 2 to 4 in the nonlinear case. In the framework of this study, the combined contribution of bottom stress and wave roller to the wave setup appears secondary since it accounts for about 10%of the predicted setup at the shoreline. Alternative computational methods are also considered to model the wave setup. In the linear case, using a spectral instead of the wave‐by‐wave approach greatly improves the wave setup predictions. This improvement is related to the disparity between the representative wave height (and thus the wave energy) obtained from spectral and wave‐by‐wave analysis when short‐wave nonlinearity becomes significant. The breaking of waves near the shore increases the mean sea level to a maximum at the shoreline. This so‐called wave setup is of fundamental importance in coastal dynamics, especially regarding flooding issues during storm events. Here, we use laboratory measurements of surface elevation and fluid velocity associated with waves propagating over a uniform beach to test the validity of wave setup predictions following two different approaches. The first one is based on the basic and common framework within which the waves are always represented by sinusoids, while the second one is based on a more elaborate and realistic representation of waves. We show that using the basic approach significantly overestimates the wave setup, while the more elaborate approach leads to more realistic predictions. Laboratory data are used to assess the validity of wave setup predictions following linear and nonlinear approachesIn a wave‐by‐wave analysis wave setup predictions are greatly improved when accounting for short‐wave nonlinearityLinear wave setup predictions are improved using spectral instead of wave‐by‐wave approach due to a correct account of the wave energy Laboratory data are used to assess the validity of wave setup predictions following linear and nonlinear approaches In a wave‐by‐wave analysis wave setup predictions are greatly improved when accounting for short‐wave nonlinearity Linear wave setup predictions are improved using spectral instead of wave‐by‐wave approach due to a correct account of the wave energy

This study presents unpublished field observations of infragravity waves, collected at the dissipative beach of Saint‐Trojan (Oléron Island, France) during the storm Kurt (3 February 2017), characterized by incident short waves of significant heights reaching 9.5 m and peak periods reaching 22 s. Data analysis reveals the development of exceptionally large infragravity waves, with significant heights reaching 1.85 m close to shore. Field observations are complemented by numerical modeling with XBeach, which well reproduces the development of such infragravity waves. Model results reveal that infragravity waves were generated mainly through the bound wave mechanism, enhanced by the development of a phase lag with the shortwave energy envelope. Spectral analysis of the free surface elevation shows the generation of superharmonic and subharmonic infragravity waves, the latter dominating the free surface elevation variance close to shore. Modeling results suggest that subharmonic infragravity waves result, at least partly, from infragravity‐wave merging, promoted by the combination of free and bound infragravity waves propagating across a several kilometer‐wide surf zone. Due to the steeper slope of the upper part of the beach profile, observed and modeled reflection coefficients under moderate‐energy show a strong tidal modulation, with a weak reflection at low tide (R2<0.2) and a full reflection at high tide (R2∼1.0). Under storm waves, the observed reflection coefficients remain unusually high for a dissipative beach (R2∼0.5−1.0), which is explained by the development of subharmonic infragravity waves with frequencies around 0.005 Hz, too long to suffer a substantial dissipation. Very large IG waves are observed at a dissipative beach under a storm, long‐period swell and are driven by the bound wave mechanismIn the surf zone, IG wave energy is transferred not only toward superharmonic but also toward subharmonic frequenciesIG wave reflection is tidally modulated and almost full at high tide due to the increase in beach slope