396 research outputs found

    Estado de conservación y características demográficas de Patella ferruginea Gmelin, 1791 (Mollusca, Gastropoda) en la Isla de Alborán (Mediterráneo occidental)

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    Due to the high risk of the global extinction in which Patella ferruginea Gmelin, 1791 is found, it is considered of great interest to describe and quantify its demographic characteristics in those sites where it still persists, as well as to evaluate the reasons which have led this limpet to be one of the most threatened marine species in the Mediterranean Sea. Over the study period (2000–2002), systematic census were made on the perimeter of the Alboran Island (Alboran Sea, westernmost area of the Mediterranean Sea) with the object to quantify the abundance of the species in the locality, as well as their external biometry and spatial distribution. As a result, the presence of a probable reproductive population of P. ferruginea was found on the island. The negative effect provoked by the continuous presence of man was proved, prejudicing the population in those zones which were more accessible for their harvesting. For this reason, it is necessary to regulate the use of the natural resources of the island to favour the conservation and spontaneous recolonisation of the zone by P. ferruginea.Dado el peligro de extinción global en el que actualmente se encuentra Patella ferruginea Gmelin, 1791, se considera de gran interés describir y cuantificar las características poblacionales de la especie en aquellas localidades donde aún persiste, así como evaluar las razones que han llevado a considerar a esta lapa como una de las especies marinas más amenazadas de extinción del Mediterráneo. Durante el período de estudio (2000–2002) fueron realizados muestreos sistemáticos en el perímetro de la Isla de Alborán (Mar de Alborán, extremo occidental del Mediterráneo) con objeto de cuantificar la abundancia de la especie en la localidad, así como su biometría externa y distribución espacial. Como resultado, se ha constatado la presencia en la isla de una población de P. ferruginea probablemente reproductora. Se ha comprobado el efecto negativo provocado por la continua presencia humana en la isla, perjudicando a la población en aquellas zonas más accesibles para la recolección de ejemplares. Es por ello que se considera necesario regular el uso de los recursos naturales en la isla con objeto de favorecer la conservación y recolonización espontánea de la localidad por P. ferruginea

    The western Mediterranean region provided the founder population of domesticated narrow-leafed lupin

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    Key message: This study revealed that the western Mediterranean provided the founder population for domesticated narrow-leafed lupin and that genetic diversity decreased significantly during narrow-leafed lupin domestication. Abstract: The evolutionary history of plants during domestication profoundly shaped the genome structure and genetic diversity of today’s crops. Advances in next-generation sequencing technologies allow unprecedented opportunities to understand genome evolution in minor crops, which constitute the majority of plant domestications. A diverse set of 231 wild and domesticated narrow-leafed lupin (Lupinus angustifolius L.) accessions were subjected to genotyping-by-sequencing using diversity arrays technology. Phylogenetic, genome-wide divergence and linkage disequilibrium analyses were applied to identify the founder population of domesticated narrow-leafed lupin and the genome-wide effect of domestication on its genome. We found wild western Mediterranean population as the founder of domesticated narrow-leafed lupin. Domestication was associated with an almost threefold reduction in genome diversity in domesticated accessions compared to their wild relatives. Selective sweep analysis identified no significant footprints of selection around domestication loci. A genome-wide association study identified single nucleotide polymorphism markers associated with pod dehiscence. This new understanding of the genomic consequences of narrow-leafed lupin domestication along with molecular marker tools developed here will assist plant breeders more effectively access wild genetic diversity for crop improvement

    Mutations in the EXT1 and EXT2 genes in Spanish patients with multiple osteochondromas

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    Multiple osteochondromas is an autosomal dominant skeletal disorder characterized by the formation of multiple cartilage-capped tumours. Two causal genes have been identified, EXT1 and EXT2, which account for 65% and 30% of cases, respectively. We have undertaken a mutation analysis of the EXT1 and EXT2 genes in 39 unrelated Spanish patients, most of them with moderate phenotype, and looked for genotype-phenotype correlations. We found the mutant allele in 37 patients, 29 in EXT1 and 8 in EXT2. Five of the EXT1 mutations were deletions identified by MLPA. Two cases of mosaicism were documented. We detected a lower number of exostoses in patients with missense mutation versus other kinds of mutations. In conclusion, we found a mutation in EXT1 or in EXT2 in 95% of the Spanish patients. Eighteen of the mutations were novel.Fil: Sarrión, P.. Universidad de Barcelona; EspañaFil: Sangorrin, A.. Hospital Sant Joan de Déu; EspañaFil: Urreizti, R.. Universidad de Barcelona; EspañaFil: Delgado, María Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Córdoba; ArgentinaFil: Artuch, R.. Hospital Sant Joan de Déu; EspañaFil: Martorell, L.. Hospital Sant Joan de Déu; EspañaFil: Armstrong, J.. Hospital Sant Joan de Déu; EspañaFil: Anton, J.. Hospital Sant Joan de Déu; EspañaFil: Torner, F.. Hospital Sant Joan de Déu; EspañaFil: Vilaseca, M. A.. Hospital Sant Joan de Déu; EspañaFil: Nevado, J.. Hospital Universitario La Paz; EspañaFil: Lapunzina, P.. Hospital Universitario La Paz; EspañaFil: Asteggiano, Carla Gabriela. Universidad Nacional de Córdoba; Argentina. Universidad Católica de Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Balcells, S.. Universidad de Barcelona; EspañaFil: Grinberg, D.. Universidad de Barcelona; Españ

    Mesoscopic mean-field theory for spin-boson chains in quantum optical systems

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    We present a theoretical description of a system of many spins strongly coupled to a bosonic chain. We rely on the use of a spin-wave theory describing the Gaussian fluctuations around the mean-field solution, and focus on spin-boson chains arising as a generalization of the Dicke Hamiltonian. Our model is motivated by experimental setups such as trapped ions, or atoms/qubits coupled to cavity arrays. This situation corresponds to the cooperative (E⊗β) Jahn-Teller distortion studied in solid-state physics. However, the ability to tune the parameters of the model in quantum optical setups opens up a variety of novel intriguing situations. The main focus of this paper is to review the spin-wave theoretical description of this problem as well as to test the validity of mean-field theory. Our main result is that deviations from mean-field effects are determined by the interplay between magnetic order and mesoscopic cooperativity effects, being the latter strongly size-dependent

    The Interspersed Spin Boson Lattice Model

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    We describe a family of lattice models that support a new class of quantum magnetism characterized by correlated spin and bosonic ordering [Phys. Rev. Lett. 112, 180405 (2014)]. We explore the full phase diagram of the model using Matrix-Product-State methods. Guided by these numerical results, we describe a modified variational ansatz to improve our analytic description of the groundstate at low boson frequencies. Additionally, we introduce an experimental protocol capable of inferring the low-energy excitations of the system by means of Fano scattering spectroscopy. Finally, we discuss the implementation and characterization of this model with current circuit-QED technology.Comment: Submitted to EPJ ST issue on "Novel Quantum Phases and Mesoscopic Physics in Quantum Gases

    Heterologous murine and bovine IVF using bottlenose dolphin (Tursiops truncatus) spermatozoa

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    Assisted reproductive technologies are of great importance for increasing the genetic diversity in captive animals. The use of bovine or murine oocytes in heterologous IVF provides advantages compared to homologous IVF in nondomestic animals, such as the accessibility to oocytes and the availability of well-developed in vitro maturation systems. The aim of this study was to determine the heterologous IVF parameters using cryopreserved dolphin spermatozoa and zona-intact bovine or murine oocytes and to examine the nuclear chromatin status of the dolphin spermatozoa. All the processes involved in the fertilization including embryo cleavage were observed by confocal microscopy and hybrid embryo formation was confirmed by polymerase chain reaction. Heterologous bovine IVF showed no polyspermy, lower percentages of pronuclear formation, and a lower cleavage rate compared to homologous IVF group (34.8% vs. 89.3%). Heterologous murine IVF showed a lower cleavage rate than homologous IVF (9.6% vs. 77.1%). With respect to dolphin sperm chromatin, it was more stable, i.e. more resistant to EDTA-SDS decondensation than the bovine sperm chromatin. This study revealed the stability of the dolphin sperm chromatin and the ability of the dolphin spermatozoa to penetrate zona-intact bovine and murine oocytes, leading to hybrid embryo formation

    Exploring the strengths and weaknesses of European innovation capacity within the Strategic Energy Technologies (SET) Plan

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    This report explored the strengths and weaknesses of the European innovation capacity within the Strategic Energy Technologies (SET) Plan Integrated Roadmap through the assessment of energy technology R&I in these specific sectors. The methodology is based on collating publicly available data and compares how the EU performs in comparison to other key countries worldwide through key indicators (e.g., patents, publications and export/import) across these 13 SET Plan themes
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