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We present the case of a patient with abdominal pain and two weeks with constipation. On physical examination, she presented abdominal distension and pain in the hypogastrium. With suspicion of intestinal obstruction and laboratory tests within normality, an abdominal CT was performed with an image of a lesion suspicious of neoplasia in sigma. After preparation with enemas, rectosigmoidoscopy was performed, which confirmed the lesion 27 centimeters from the anal margin, obstructive, non-passable, and not allowing stent placement., Presentamos el caso de una paciente con cuadro de dolor abdominal y estreñimiento de dos semanas de evolución. Presenta distensión abdominal y dolor en hipogastrio. Con analítica dentro de la normalidad de se realiza TC de abdomen con imagen de lesión sospechosa de neoplasia en sigma. Se realiza rectosigmoidoscopia que confirma la lesión a 27 centímetros del margen anal, obstructiva, no franqueable y que no permite la colocación de stent.

Arbuscular mycorrhizal fungi (AMF) can prime plant defences increasing their resistance against pathogens and insect herbivores. Using tomato as a model, we have shown that inoculation with different AMF reduces the performance of the chewing herbivore Spodoptera exigua and the leaf miner Tuta absoluta. Transcriptomic and metabolomics analyses revealed that this Mycorrhiza Induced Resistance (MIR) is associated to boosted activation of plant direct and indirect defences in response to the attackers. We found primed accumulation in attacked leaves of antiherbivore metabolites, including alkaloids and polyamine conjugates, and functional analyses demonstrated that some of the identified compounds significantly inhibit herbivore development. In addition, the symbiosis altered the volatile blends released by the plant, and enhanced the attraction of natural enemies of the pests (Nesidiocoris tenuis, commonly used in biocontrol programs). Finally, networks analyses allowed the identification of key regulators of the primed response within the jasmonic acid and ethylene signalling pathways. Despite the many studies showing induced resistance by microorganisms in different plant‐pest systems, the variability in the protection achieved under agronomic settings is hindering the application of this strategy in agriculture. Plant‐microbe‐herbivore interactions are highly context dependent, with multiple biotic and abiotic factors influencing the final output. Identifying such factors is essential to optimize the application of microbial inoculants for crop protection in agriculture. We found that the plant genotype and nutrient availability are important drivers of the context dependency of MIR in tomato. Despite of the variability, comparisons across different experimental scales, from controlled lab set‐ups to commercial production conditions, confirmed that MIR can be achieved under crop production conditions and is compatible with other biocontrol methods. Accordingly, MIR

The use of arbuscular mycorrhizal (AM) fungi has great potential, being used as biostimulants, biofertilizers and bioprotection agents in agricultural and natural ecosystems. However, the application of AM fungal inoculants is still challenging due to the variability of results when applied in production systems. This variability is partly due to differences in symbiosis establishment. Reducing such variability and promoting symbiosis establishment is essential to improve the efficiency of the inoculants. In addition to strigolactones, flavonoids have been proposed to participate in the pre-symbiotic plant-AM fungus communication in the rhizosphere, although their role is still unclear. Here, we studied the specific function of flavonoids as signaling molecules in AM symbiosis. For that, both in vitro and in planta approaches were used to test the stimulatory effect of an array of different subclasses of flavonoids on Rhizophagus irregularis spore germination and symbiosis establishment, using physiological doses of the compounds. We show that the flavone chrysin and the flavonols quercetin and rutin were able to promote spore germination and root colonization at low doses, confirming their role as pre-symbiotic signaling molecules in AM symbiosis. The results pave the way to use these flavonoids in the formulation of AM fungal-based products to promote the symbiosis. This can improve the efficiency of commercial inoculants, and therefore, help to implement their use in sustainable agriculture.

Compressed sensing has become a widely accepted paradigm to construct high dimensional cluster expansion models used for statistical mechanical studies of atomic configuration in complex multicomponent crystalline materials. However, strict sampling requirements necessary to obtain minimal coherence measurements for compressed sensing to guarantee accurate estimation of model parameters are difficult and in some cases impossible to satisfy due to the inability of physical systems to access certain configurations. Nevertheless, the dependence of energy on atomic configuration can still be adequately learned without these strict requirements by using compressed sensing by way of coherent measurements using redundant function sets known as frames. We develop a particular frame constructed from the union of all occupancy-based cluster expansion basis sets. We illustrate how using this highly redundant frame yields sparse expansions of the configuration energy of complex oxide materials that are competitive and often surpass the prediction accuracy and sparsity of models obtained from standard cluster expansions.

Disordered multicomponent systems attract great interest due to their engineering design flexibility and subsequent rich space of properties. However, detailed characterization of the structure and atomic correlations remains challenging and hinders full navigation of these complex spaces. A lattice cluster expansion is one tool to obtain configurational and energetic resolution. While in theory a cluster expansion can be applied to any system of any dimensionality, the method has primarily been used in binary systems or ternary alloys. Here we apply cluster expansions in high-component ionic systems, setting up the largest cluster expansion ever attempted to our knowledge. In doing so, we address and discuss challenges specific to high-component ionic systems, namely charge state assignments, structural relaxations, and rank-deficient systems. We introduce practical procedures to make the fitting and analysis of complex systems tractable, providing guidance for future computational studies of disordered ionic systems.

We introduce ℓ0ℓ2-norm regularization and hierarchy constraints into linear regression for the construction of cluster expansions to describe configurational disorder in materials. The approach is implemented through mixed integer quadratic programming (MIQP). The ℓ2-norm regularization is used to suppress intrinsic data noise, while the ℓ0-norm is used to penalize the number of nonzero elements in the solution. The hierarchy relation between clusters imposes relevant physics and is naturally included by the MIQP paradigm. As such, sparseness and cluster hierarchy can be well optimized to obtain a robust, converged set of effective cluster interactions with improved physical meaning. We demonstrate the effectiveness of ℓ0ℓ2-norm regularization in two high-component disordered rocksalt cathode material systems, where we compare the cross-validation, convergence speed, and the reproduction of phase diagrams, voltage profiles, and Li-occupancy energies with those of the conventional ℓ1-norm regularized cluster expansion models.

Altres ajuts: The sedimentological, micromorphological and part of the radiocarbon analyses were funded by subproject C1 of the CRC 806 "Our way to Europe" (DFG, German Research Foundation) and the Marie Curie Intra European Fellowship project 'Hiatus LPleis Iberia' (FP7-2013-IEF-628179). We gratefully acknowledge contributions made by the wide excavation and laboratory team. Fieldworks at Peña Capón were authorized by the Dirección General de Cultura de la Junta de Comunidades de Castilla-La Mancha (Spain) (Exp. 14.0955-P4 and Exp.: 19.248) with permission from the Confederación Hidrográfica del Tajo., As the south-westernmost region of Europe, the Iberian Peninsula stands as a key area for understanding the process of modern human dispersal into Eurasia. However, the precise timing, ecological setting and cultural context of this process remains controversial concerning its spatiotemporal distribution within the different regions of the peninsula. While traditional models assumed that the whole Iberian hinterland was avoided by modern humans due to ecological factors until the retreat of the Last Glacial Maximum, recent research has demonstrated that huntergatherers entered the Iberian interior at least during Solutrean times. We provide a multi-proxy geoarchaeological, chronometric and paleoecological study on human-environment interactions based on the key site of Peña Capón (Guadalajara, Spain). Results show (1) that this site hosts the oldest modern human presence recorded to date in central Iberia, associated to pre-Solutrean cultural traditions around 26,000 years ago, and (2) that this presence occurred during Heinrich Stadial 2 within harsh environmental conditions. These findings demonstrate that this area of the Iberian hinterland was recurrently occupied regardless of climate and environmental variability, thus challenging the widely accepted hypothesis that ecological risk hampered the human settlement of the Iberian interior highlands since the first arrival of modern humans to Southwest Europe.

Algal turfs are ecosystem engineers receiving steadily growing attention in recent years in relation to their expansion on temperate reefs due to global change. However, their species diversity and taxonomy are still poorly understood, mostly based solely on morphological information. Algal turfs are the dominant type of assemblage in Macaronesia, but molecular diversity surveys have barely been applied in this region. We aim to show how molecular tools can assist us to improve our understanding of the diversity and taxonomy of natural algal turfs by studying the turf-forming rhodomelacean genus Stichothamnion which has only one recognized species in Macaronesia, the generitype S. cymatophilum. Stichothamnion resembles other members of the tribe Streblocladieae, but it has unbranched trichoblasts, an unusual character in the family. Here, we show using phylogenetic analyses of the rbcL gene that specimens collected in the Canary Islands and the Azores identifiable morphologically as S. cymatophilum exhibit cryptic diversity, and these analyses position Stichothamnion in the Vertebrata clade with full support. We place Stichothamnion in synonymy with Vertebrata, transfer the existing species, and describe a newly discovered cryptic species as V. barbarae Muñoz-Luque & Díaz-Tapia, sp. nov., found exclusively in the Azores. The new species was morphologically indistinguishable from V. cymatophila but diverged by 2.1–2.3% in the rbcL gene. This study illustrates the work required to better understand the extraordinary species diversity in algal turfs such as those in Macaronesia which remain taxonomically under-studied.