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Con el diseño y la construcción del Emerald Necklace de Boston de Frederick Law Olmsted (1822-1903) tomaba forma una nueva herramienta urbanística directamente dirigida a adaptar el paisaje natural en el interior de la ciudad, concebida como sistema de parques, fusionando estructura urbana y diseño del paisaje. La idea sigue siendo esencial para pensar en una simbiosis entre ciudad y naturaleza. Sin ser exhaustivos, comprobamos como la idea se introduce en Europa de manera diversa y con logros dispares. A través de tres ‘paisajistas’ de generaciones que se suceden en el siglo XX, arraigados en contextos y lugares diferentes, queremos mostrar cómo el sistema de parques se consolida en Europa con perspectivas distintas aunque complementarias y que contribuyen a construir en la cultura urbano arquitectónica un camino de interacción entre ciudad y naturaleza, precedente directo de lo que hoy denominamos Green infrastructure. With the design and construction of the Emerald Necklace in Boston by Frederick Law Olmsted (1822-1903), a new urban tool took shape directly targeted at adapting natural landscapes to the interior of a city, conceptualized as a system of parks fused within an urban structure and landscape design. This idea continues to be key to the development process of creating symbiosis between city and nature. Without claiming to be exhaustive, this paper reviews how this idea was introduced to Europe in a variety of ways and through diverse achievements. Through three 20th century “landscapers” rooted in different contexts and places, this paper aims to show how systems of parks have consolidated in Europe with distinctive yet complimentary points-of-views, all contributing to the development of the interaction between city and nature in urban architectural culture, laying the foundation of what is presently called Green Infrastructure.

Fossils of juvenile Mesozoic birds provide insight into the early evolution of avian development, however such fossils are rare. The analysis of the ossification sequence in these early-branching birds has the potential to address important questions about their comparative developmental biology and to help understand their morphological evolution and ecological differentiation. Here we report on an early juvenile enantiornithine specimen from the Early Cretaceous of Europe, which sheds new light on the osteogenesis in this most species-rich clade of Mesozoic birds. Consisting of a nearly complete skeleton, it is amongst the smallest known Mesozoic avian fossils representing post-hatching stages of development. Comparisons between this new specimen and other known early juvenile enantiornithines support a clade-wide asynchronous pattern of osteogenesis in the sternum and the vertebral column, and strongly indicate that the hatchlings of these phylogenetically basal birds varied greatly in size and tempo of skeletal maturation.

Although some acidophilic and alkaliphilic species have been described recently, most of the known sulfate-reducing bacteria (SRB) grow optimally at neutral pH. In this study, sulfate reduction was studied with sediment samples from the extremely acidic Tinto River basin. Stable enrichments of SRB were obtained at pH¿4 with glycerol, methanol and hydrogen; at pH¿4.5 with lactate and at pH¿5.5 with succinate as substrates. Inhibition of sulfate reduction by organic acids below their pKa was observed. Cloning and sequencing of 16S rRNA gene showed that fermentative bacteria (Paludibacter spp., Oscillibacter spp.) and SRB (Thermodesulfobium spp., Desulfosporosinus spp., Desulfitobacterium spp., Desulfotomaculum spp.) were co-enriched. By repeated serial dilutions and streaking on agar plates, four strains of SRB belonging to the Firmicutes phylum were obtained. Two of them show 96% 16S rRNA gene sequence similarity with Desulfosporosinus acidophilus, and a third one with Desulfosporosinus orientis. Another isolate has just 93% rRNA gene sequence similarity with the Desulfosporosinus/Desulfitobacterium cluster and might represent a novel species within a novel genus. One of the Desulfosporosinus strains was further investigated showing maximum growth at pH¿5.5, and a pH-dependent inhibitory effect of organic acids and sulfide

Recently acquired swath-bathymetry data and high-resolution seismic reflection profiles offshore Adra (Almería, Spain) reveal the surficial expression of a NW–SE trending 20 km-long fault, which we termed the Adra Fault. Seismic imaging across the structure depicts a subvertical fault reaching the seafloor surface and slightly dipping to the NE showing an along-axis structural variability. Our new data suggest normal displacement of the uppermost units with probably a lateral component. Radiocarbon dating of a gravity core located in the area indicates that seafloor sediments are of Holocene age, suggesting present-day tectonic activity. The NE Alboran Sea area is characterized by significant low-magnitude earthquakes and by historical records of moderate magnitude, such as the Mw = 6.1 1910 Adra Earthquake. The location, dimension and kinematics of the Adra Fault agree with the fault solution and magnitude of the 1910 Adra Earthquake, whose moment tensor analysis indicates normal-dextral motion. The fault seismic parameters indicate that the Adra Fault is a potential source of large magnitude (Mw = 6.5) earthquakes, which represents an unreported seismic hazard for the neighbouring coastal areas.

International audience; We have considered the problem of detection and estimation of compact sources immersed in a background plus instrumental noise. Sparse approximation to signals deals with the problem of finding a representation of a signal as a linear combination of a small number of elements from a set of signals called dictionary. The estimation of the signal leads to a minimization problem for the amplitude associated to the sources. We have developed a methodology that minimizes the lp-norm with a constraint on the goodness-of-fit and we have compared different norms against the matched filter.