Preface

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Characterization of reciprocity gaps from interference tests in fractured media through a dual porosity model

We analyze drawdown reciprocity gaps emerging in interference tests performed in a confined fissured karstic formation. Modeling the system as a dual porosity continuum allows characterizing the dynamics of the relative contribution of the connected fractures and the rock matrix to the total flow rate extracted at the pumping wells. Observed lack of reciprocity of drawdowns can then be linked to the occurrence of processes that are not accounted for in the classical flow models based on a single-continuum representation of the system through flow equations grounded on Darcy's law only. We show that interpreting the system as a dual porosity continuum can cause drawdown reciprocity gaps to emerge as a consequence of local effects associated with an identifiable contribution of the matrix to the total fluid extracted at the well location during pumping. These theoretical results are then employed to identify the contribution to the flow being supplied to the pumping well by the low conductivity matrix constituting the host rock formation, in contrast to that provided by the fractures. An application to data from two interference tests performed at the Hydrogeological Experimental Site (HES) in Poitiers, France, illustrates the approach. We show that, whenever the matrix is assumed to provide a contribution to the total flow rate extracted, nonreciprocity is expected, the latter being linked to the occurrence of a differential drawdown between fracture and matrix at the pumping well. This difference decreases with time in the example presented, displaying a power law late time behavior, with nonreciprocity effects persisting up to remarkably long times

Cortinarius mahiquesii, a new subhypogeous species from Catalonia (Iberian Peninsula)

We describe and comment on a new species of Cortinarius (Basidiomycota), C. mahiquesii, collected in a pure Cistus monspeliensis scrub community in Catalonia (NE of the Iberian Peninsula). Drawings of microscopic characters, scanning microphotographs of the basidiospores, and colour pictures of the basidiomes in their natural habitat are provided. A molecular analysis was carried out to characterize the new species using ITS sequences

Radical Cyclization of Trichloroacetamides: Synthesis of Lactams

Trichloroacetamides can act as radical precursors to synthesize nitrogen-containing heterocycles in a variety of processes, mainly involving atom transfer radical cyclizations (ATRC), mediated by Cu(I) or Ru(II) catalysts, and the hydride reductive method, employing either Bu3SnH or (Me3Si)3SiH, or recently NaBH3CN. Additionally, amine-mediated single-electron transfer cyclizations, as well as radical processes promoted by Ni, Fe, Mn, Ti, and Ag, have been developed

Microplate tectonics and environmental factors as distribution drivers in Western Mediterranean freshwater planarians

AIM: Species biogeography mainly focuses on palaeogeographical events, while environmental factors are generally overlooked despite their importance in species diversification. Here, we use an integrative approach to understand how palaeogeographical and environmental processes shape species distribution and focus on freshwater planarians as the model system. LOCATION: Western Mediterranean. TAXON: Dugesia METHODS: We inferred the phylogenetic relationships of most known Dugesia species in the area using six molecular markers. We then estimated their divergence times and reconstructed their ancestral distribution ranges. We also performed environmental niche modelling analyses using Dugesia subtentaculata as a model to evaluate the effects of several hydro-environmental variables and the likely existence of interspecific competition on Dugesia distributions. RESULTS: Our results provide a new phylogenetic scheme for Dugesia from the Western Mediterranean and show that the time splits between the lineages and their putative ancestral distribution ranges are correlated with microplate tectonic dynamics within the region during the Oligocene–Miocene period. Our environmental niche modelling analyses indicate that the type of land cover and the slope of the terrain are the most important abiotic factors driving the distribution of Dugesia from this region. Finally, we found a partial niche overlap between D. subtentaculata and two other common planarian species from the Iberian Peninsula. MAIN CONCLUSIONS: The microplate tectonic dynamics of the Western Mediterranean during the Oligocene–Miocene period, together with the position of the mountain ranges and posterior climate changes, may have played crucial roles in driving the biogeographical history of Dugesia in this region. Moreover, both interspecific competition and changes in fluvial characteristics driven by human activities may affect the current diversity and distribution of Dugesia in the Western Mediterranean. This study highlights the importance of integrating different types of information to study the biogeographical history of a species. <br