The role of pressure on the magnetism of bilayer graphene

We study the effect of pressure on the localized magnetic moments induced by vacancies in bilayer graphene in the presence of topological defects breaking the bipartite nature of the lattice. By using a mean-field Hubbard model we address the two inequivalent types of vacancies that appear in the Bernal stacking bilayer graphene. We find that by applying pressure in the direction perpendicular to the layers the critical value of the Hubbard interaction needed to polarize the system decreases. The effect is particularly enhanced for one type of vacancies, and admits straightforward generalization to multilayer graphene in Bernal stacking and graphite. The present results clearly demonstrate that the magnetic behavior of multilayer graphene can be affected by mechanical transverse deformation

Magnetic moments in the presence of topological defects in graphene

We study the influence of pentagons, dislocations and other topological defects breaking the sublattice symmetry on the magnetic properties of a graphene lattice in a Hartree Fock mean field scheme. The ground state of the system with a number of vacancies or similar defects belonging to the same sublattice is known to have total spin equal to the number of uncoordinated atoms in the lattice for any value of the Coulomb repulsion U according to the Lieb theorem. We show that the presence of a single pentagonal ring in a large lattice is enough to alter this behavior and a critical value of U is needed to get the polarized ground state. Glide dislocations made of a pentagon-heptagon pair induce more dramatic changes on the lattice and the critical value of U needed to polarize the ground state depends on the density and on the relative position of the defects. We found a region in parameter space where the polarized and unpolarized ground states coexist.Comment: 5 pages, 3 figure

Insights on Salt Tolerance of Two Endemic Limonium Species from Spain

[EN] We have analysed the salt tolerance of two endemic halophytes of the genus Limonium, with high conservation value. In the present study, seed germination and growth parameters as well as different biomarkers-photosynthetic pigments, mono and divalent ion contents-associated to salt stress were evaluated in response to high levels of NaCl. The study was completed with an untargeted metabolomics analysis of the primary compounds including carbohydrates, phosphoric and organic acids, and amino acids, identified by using a gas chromatography and mass spectrometry platform. Limonium albuferae proved to be more salt-tolerant than L. doufourii, both at the germination stage and during vegetative growth. The degradation of photosynthetic pigments and the increase of Na+/K+ ratio under salt stress were more accentuated in the less tolerant second species. The metabolomics analysis unravelled several differences between the two species. The higher salt tolerance of L. albuferae may rely on its specific accumulation of fructose and glucose under high salinity conditions, the first considered as a major osmolyte in this genus. In addition, L. albuferae showed steady levels of citric and malic acids, whereas the glutamate family pathway was strongly activated under stress in both species, leading to the accumulation of proline (Pro) and gamma-aminobutyric acid (GABA).This research was funded by GENERALITAT VALENCIANA, grant number AICO/2017/039, to M. Boscaiu.González-Orenga, S.; Ferrer-Gallego, PP.; Laguna, E.; López-Gresa, MP.; Donat-Torres, MP.; Verdeguer Sancho, MM.; Vicente, O.... (2019). Insights on Salt Tolerance of Two Endemic Limonium Species from Spain. Metabolites. 9(12):1-22. https://doi.org/10.3390/metabo9120294S12291

Microbiota Sensing by Mincle-Syk Axis in Dendritic Cells Regulates Interleukin-17 and -22 Production and Promotes Intestinal Barrier Integrity

We are grateful to members of the D.S. laboratory and Dr. E. Fernández-Malavé for discussions and critical reading of the manuscript. We appreciate the support of A. Tomás-Loba, G. Sabio, P. Martín, A. Tsilingiri, A.R. Ramiro, C.L. Abram, C.A. Lowell, J.M. García-Lobo, M. Molina, and M.C. Rodríguez for providing reagents and support. We thank the staff at the Fundación Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC) facilities for technical support. M.M.-L. received a Formación de Personal Universitario (FPU) fellowship (AP2010-5935) from the Spanish Ministerio de Educación. S.I. is funded by grant SAF2015-74561-JIN from the Spanish Ministerio de Ciencia, Innovación, y Universidades (MCIU) and Fondos Europeos de Desarrollo Regional (FEDER). G.D.B and D.M.R. are supported by the Wellcome Trust and the MRC Centre for Medical Mycology at the University of Aberdeen. S.L.L. is supported by the Swiss National Science Foundation (PP00P3_150758). Work in the D.S. laboratory is funded by the CNIC and grant SAF2016-79040-R from MCIU, the Agencia Estatal de Investigación, and FEDER; B2017/BMD-3733 Immunothercan-CM from Comunidad de Madrid; RD16/0015/0018-REEM from FIS-Instituto de Salud Carlos III, MCIU, and FEDER; the Acteria Foundation; the Constantes y Vitales prize (Atresmedia); La Marató de TV3 Foundation (201723); the European Commission (635122-PROCROP H2020), and the European Research Council (ERC-2016-Consolidator Grant 725091). The CNIC is supported by the MCIU and the Pro-CNIC Foundation and is a Severo Ochoa Center of Excellence (SEV-2015-0505).Peer reviewedPublisher PD

A genome-wide association study follow-up suggests a possible role for PPARG in systemic sclerosis susceptibility

Introduction: A recent genome-wide association study (GWAS) comprising a French cohort of systemic sclerosis (SSc) reported several non-HLA single-nucleotide polymorphisms (SNPs) showing a nominal association in the discovery phase. We aimed to identify previously overlooked susceptibility variants by using a follow-up strategy.<p></p> Methods: Sixty-six non-HLA SNPs showing a P value <10-4 in the discovery phase of the French SSc GWAS were analyzed in the first step of this study, performing a meta-analysis that combined data from the two published SSc GWASs. A total of 2,921 SSc patients and 6,963 healthy controls were included in this first phase. Two SNPs, PPARG rs310746 and CHRNA9 rs6832151, were selected for genotyping in the replication cohort (1,068 SSc patients and 6,762 healthy controls) based on the results of the first step. Genotyping was performed by using TaqMan SNP genotyping assays. Results: We observed nominal associations for both PPARG rs310746 (PMH = 1.90 × 10-6, OR, 1.28) and CHRNA9 rs6832151 (PMH = 4.30 × 10-6, OR, 1.17) genetic variants with SSc in the first step of our study. In the replication phase, we observed a trend of association for PPARG rs310746 (P value = 0.066; OR, 1.17). The combined overall Mantel-Haenszel meta-analysis of all the cohorts included in the present study revealed that PPARG rs310746 remained associated with SSc with a nominal non-genome-wide significant P value (PMH = 5.00 × 10-7; OR, 1.25). No evidence of association was observed for CHRNA9 rs6832151 either in the replication phase or in the overall pooled analysis.<p></p> Conclusion: Our results suggest a role of PPARG gene in the development of SSc

Improving Scientific Knowledge of Mallorca Channel Seamounts (Western Mediterranean) within the Framework of Natura 2000 Network

The scientific exploration of Mallorca Channel seamounts (western Mediterranean) is improving the knowledge of the Ses Olives (SO), Ausias March (AM), and Emile Baudot (EB) seamounts for their inclusion in the Natura 2000 network. The aims are to map and characterize benthic species and habitats by means of a geological and biological multidisciplinary approach: high-resolution acoustics, sediment and rock dredges, beam trawl, bottom trawl, and underwater imagery. Among the seamounts, 15 different morphological features were differentiated, highlighting the presence of 4000 pockmarks, which are seafloor rounded depressions indicators of focused fluid flow escapes, usually gas and/or water, from beneath the seabed sediments. So far, a total of 547 species or taxa have been inventoried, with sponges, fishes, mollusks, and crustaceans the most diverse groups including new taxa and new geographical records. Up to 29 categories of benthic habitats have been found, highlighting those included in the Habitats Directive: maërl beds on the summits of AM and EB, pockmarks around the seamounts and coral reefs in their rocky escarpments as well as fields of Isidella elongata on sedimentary bathyal bottoms. Trawling is the main demersal fishery developed around SO and AM, which are targeted to deep water crustaceans: Parapenaeus longirostris, Nephrops norvegicus, and Aristeus antennatus. This study provides scientific information for the proposal of the Mallorca Channel seamounts as a Site of Community Importance and for its final declaration as a Special Area of Conservation

Gauge fields and curvature in graphene

The low energy excitations of graphene can be described by a massless Dirac equation in two spacial dimensions. Curved graphene is proposed to be described by coupling the Dirac equation to the corresponding curved space. This covariant formalism gives rise to an effective hamiltonian with various extra terms. Some of them can be put in direct correspondence with more standard tight binding or elasticity models while others are more difficult to grasp in standard condensed matter approaches. We discuss this issue, propose models for singular and regular curvature and describe the physical consequences of the various proposals.Comment: Proceedings of the International Conference on Theoretical Physics: Dubna-Nano2008 to be published online in Journal of Physics: Conference serie

2013. Documento Sevilla de Consenso sobre Alternativas a la Transfusión de Sangre Alogénica. Actualización del Documento Sevilla

La transfusión de sangre alogénica (TSA) no es inocua, y como consecuencia han surgido múltiples alternativas a la misma (ATSA). Existe variabilidad respecto a las indicaciones y buen uso de las ATSA. Dependiendo de la especialidad de los médicos que tratan a los pacientes, el grado de anemia, la política transfusional, la disponibilidad de las ATSA y el criterio personal, estas se usan de forma variable. Puesto que las ATSA tampoco son inocuas y pueden no cumplir criterios de coste-efectividad, la variabilidad en su uso es inaceptable. Las sociedades españolas de Anestesiología y Reanimación (SEDAR), Hematología y Hemoterapia (SEHH), Farmacia Hospitalaria (SEFH), Medicina Intensiva y Unidades Coronarias (SEMICYUC), Trombosis y Hemostasia (SETH) y Transfusiones Sanguíneas (SETS) han elaborado un documento de consenso para el buen uso de la ATSA. Un panel de expertos de las 6 sociedades ha llevado a cabo una revisión sistemática de la literatura médica y elaborado el 2013. Documento Sevilla de Consenso sobre Alternativas a la Transfusión de Sangre Alogénica. Solo se contempla las ATSA dirigidas a disminuir la transfusión de concentrado de hematíes. Se definen las ATSA como toda medida farmacológica y no farmacológica encaminada a disminuir la transfusión de concentrado de hematíes, preservando siempre la seguridad del paciente. La cuestión principal que se plantea en cada ítem se formula, en forma positiva o negativa, como: «La ATSA en cuestión reduce/no reduce la tasa transfusional». Para formular el grado de recomendación se ha usado la metodología Grades of Recommendation Assessment, Development and Evaluation (GRADE)

Cross-disease Meta-analysis of Genome-wide Association Studies for Systemic Sclerosis and Rheumatoid Arthritis Reveals IRF4 as a New Common Susceptibility Locus

Objectives: Systemic sclerosis (SSc) and rheumatoid arthritis (RA) are autoimmune diseases that share clinical and immunological characteristics. To date, several shared SSc- RA loci have been identified independently. In this study, we aimed to systematically search for new common SSc-RA loci through an inter-disease meta-GWAS strategy. Methods: We performed a meta-analysis combining GWAS datasets of SSc and RA using a strategy that allowed identification of loci with both same-direction and opposingdirection allelic effects. The top single-nucleotide polymorphisms (SNPs) were followed-up in independent SSc and RA case-control cohorts. This allowed us to increase the sample size to a total of 8,830 SSc patients, 16,870 RA patients and 43,393 controls. Results: The cross-disease meta-analysis of the GWAS datasets identified several loci with nominal association signals (P-value < 5 x 10-6), which also showed evidence of association in the disease-specific GWAS scan. These loci included several genomic regions not previously reported as shared loci, besides risk factors associated with both diseases in previous studies. The follow-up of the putatively new SSc-RA loci identified IRF4 as a shared risk factor for these two diseases (Pcombined = 3.29 x 10-12). In addition, the analysis of the biological relevance of the known SSc-RA shared loci pointed to the type I interferon and the interleukin 12 signaling pathways as the main common etiopathogenic factors. Conclusions: Our study has identified a novel shared locus, IRF4, for SSc and RA and highlighted the usefulness of cross-disease GWAS meta-analysis in the identification of common risk loci

Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2

The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality