180 research outputs found

    Líquenes de interés corológico del Parque Natural “Serra da Enciña da Lastra” (Ourense, Galicia, España)

    Get PDF
    Se mencionan 15 especies de líquenes del Parque Natural “Serra da Enciña da Lastra”, de las que 6: Fulgensia fulgens (Sw.) Elenkin, Melanelixia glabra (Schaer.) O. Blanco, A. Crespo, Divakar, Essl., D. Hawksw. & Lumbsch, Phaeophyscia sciastra (Ach.) Moberg, Psora decipiens (Hedw.) Hoffm., Psora testacea Hoffm. y Psora vallesiaca (Schaerer) Timdal son nuevas citas para Galicia. Las 9 restantes lo son para la provincia de Ourense

    Nuevas citas de líquenes del Parque Natural “Serra da Enciña da Lastra” (Ourense, Galicia, España)

    Get PDF
    Se mencionan 25 especies de líquenes del Parque Natural “Serra da Enciña da Lastra”, de las que son nuevas citas para Galicia: Acarospora murorum, Cetraria merrillii, Lecanora crenulata, Lecidella patavina, Placynthiella oligotropha, Placynthium lismorense, Scoliciosporum chlorococcum, Trapeliopsis wallrothii, Verrucaria calciseda y Verrucaria lecideoides. Las otras 15 son nuevas citas para la provincia de Ourense

    Los géneros foliáceos de la familia Physciaceae (Lichenes, Ascomycota) en el herbario PO (Universidade de Porto, Portugal)

    Get PDF
    Presentamos los resultados de la revisión de los 116 pliegos de biotipo foliáceo de la familia Physciaceae depositados en el herbario PO de la Universidad de Porto, Portugal. Esta revisión nos permitió sinonimizar Physcia caesia var. perrugosa a P. aipolia, aportar la cita de Physconia grisea ssp. lilacina para Portugal y confirmar la única cita de Phaeophyscia sciastra

    A Morphometric Analysis of the Santolina chamaecyparissus Complex (Asteraceae)

    Get PDF
    The genus Santolina (Asteraceae, Anthemideae) includes 26 species of aromatic evergreen shrubs endemic to the western Mediterranean Basin. Santolina is widely used as ornamental plant, in xerigardening, and in ethnobotany. The Santolina chamaecyparissus complex, including about half of the known species diversity, has been properly investigated on systematic and taxonomic grounds only recently, and a complete morphometric study is still missing. Here we provide a morphometric characterization and comparison of all the 14 species of this complex, using both univariate and multivariate analyses. Our results suggest that species of this complex can be distinguished using combinations of quantitative and qualitative character-states, mostly related to the leaf morphology. The analysis of S. villosa, a tetraploid/hexaploid Spanish endemic, showed that the two cytotypes cannot be safely identified based on morphology. Coupling this evidence with available phylogenetic information, we conclude that there is no reason to split the two cytotypes of S. villosa in two distinct taxa. An identification key for all the species of the complex is presented

    Thermal Properties and Segregation Behavior of Pt Nanowires Modified with Au, Ag, and Pd Atoms: A Classical Molecular Dynamics Study

    Get PDF
    Platinum nanowires (NWs) have been reported to be catalytically active toward the oxygen reduction reaction (ORR). The edge modification of Pt NWs with metals M (M = Au, Ag, or Pd) may have a positive impact on the overall ORR activity by facilitating diffusion of adsorbed oxygen, Oads, and hydroxyl groups, OHads, between the {001} and {111} terraces. In the present study, we have employed classical molecular dynamics simulations to investigate the segregation behavior of Au, Ag, and Pd decorating the edges of Pt NWs. We observe that, under vacuum conditions, Pd prefers to diffuse toward the core rather than stay on the NW surface. Ag and Au atoms are mobile at temperatures as low as 900 K; they remain on the surface but do not appear to be preferentially more stable at edge sites. To effect segregation of Au and Ag atoms toward the edge, we propose annealing in the presence of different reactive gas environments. Overall, our study suggests potential experimental steps required for the synthesis of Pt nanowires and nanoparticles with improved Oads and OHads interfacet diffusion rates and consequently an improved ORR activity

    Adenovirus type 7 associated with severe and fatal acute lower respiratory infections in Argentine children

    Get PDF
    BACKGROUND: Adenoviruses are the second most prevalent cause of acute lower respiratory infection of viral origin in children under four years of age in Buenos Aires, Argentina. The purpose of this study was to analyze the clinical features and outcome of acute lower respiratory infection associated with different adenovirus genotypes in children. METHODS: Twenty-four cases of acute lower respiratory infection and adenovirus diagnosis reported in a pediatric unit during a two-year period were retrospectively reviewed. Adenovirus was detected by antigen detection and isolation in HEp-2 cells. Adenovirus DNA from 17 isolates was studied by restriction enzyme analysis with Bam HI and Sma I. RESULTS: Subgenus b was found in 82.3% of the cases, and subgenus c in 17.7%. Within subgenus b, only genotype 7 was detected, with genomic variant 7h in 85.7% (12/14) and genomic variant 7i in 14.3% (2/14). Mean age was 8.8 ±; 6 months, and male to female ratio was 3.8: 1. At admission, pneumonia was observed in 71% of the cases and bronchiolitis in 29%. Malnutrition occurred in 37% of the cases; tachypnea in 79%; chest indrawing in 66%; wheezing in 58%; apneas in 16%; and conjunctivitis in 29%. Blood cultures for bacteria and antigen detection of other respiratory viruses were negative. During hospitalization, fatality rate was 16.7% (4 /24). Of the patients who died, three had Ad 7h and one Ad 7i. Thus, fatality rate for adenovirus type 7 reached 28.6% (4/14). CONCLUSIONS: These results show the predominance of adenovirus 7 and high lethality associated with the genomic variants 7h and 7i in children hospitalized with acute lower respiratory infection

    El Macizo Central orensano (LIC, Lugar de Importancia Comunitaria) área de especial importancia para la conservación de la flora liquénica en Galicia

    Get PDF
    Se señala la presencia en el Macizo orensano de 215 especies liquénicas, 21 de las cuales son desconocidas en el resto del territorio gallego. En esta zona se presenta también un gran número de taxones amenazados. Por ello, consideramos el LIC una importante área de conservación de la diversidad liquénica en Galicia

    The (ir)relevance of the abandoned criterion II for the diagnosis of serrated polyposis syndrome:a retrospective cohort study

    Get PDF
    The World Health Organization (WHO) recently updated the diagnostic criteria for serrated polyposis syndrome (SPS). One of the three previous diagnostic criteria (criterion II 2010) is now abandoned: ≥ 1 serrated polyp (SP) proximal to the sigmoid in a first-degree relative (FDR) of a patient with SPS. Individuals fulfilling this abandoned criterion now receive the same surveillance recommendations as all FDRs of patients with SPS. We aimed to compare the incidence of advanced neoplasia (AN) in FDRs with vs. without fulfillment of the abandoned criterion II 2010. We retrospectively recruited FDRs of patients with SPS who underwent a colonoscopy, and stratified them according to fulfilment of criterion II 2010 at baseline. Our primary and secondary outcomes were AN incidence during surveillance and at baseline, respectively. We included 224 FDRs of patients with SPS, of whom 36 (16%) fulfilled criterion II 2010 at baseline. One hundred and five underwent surveillance after baseline. Criterion II 2010-positive FDRs were at increased risk of AN, both during surveillance (hazard ratio 8.94, 95% CI 2.15–37.1, p =.003) as well as at baseline (adjusted odds-ratio 9.30, 95% CI 3.7–23.3, p <.001). FDRs of patients with SPS that underwent colonoscopy and fulfilled the abandoned criterion II 2010 for SPS diagnosis were at increased risk of AN at baseline and during surveillance in this small, retrospective cohort study. Our results should be interpreted with caution but suggest that adherence to surveillance recommendations for all FDRs of patients with SPS is important, especially for those that would have fulfilled the now abandoned criterion II 2010

    Mixing thermodynamics and electronic structure of the Pt1−xNix (0 ≤ x ≤ 1) bimetallic alloy

    Get PDF
    The development of affordable bifunctional platinum alloys as electrode materials for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) remains one of the biggest challenges for the transition towards renewable energy sources. Yet, there is very little information on the optimal ratio between platinum and the transition metal used in the alloy and its impact on the electronic properties. Here, we have employed spin-polarised density functional simulations with long-range dispersion corrections [DFT–D3–(BJ)], to investigate the thermodynamics of mixing, as well as the electronic and magnetic properties of the Pt1−xNix solid solution. The Ni incorporation is an exothermic process and the alloy composition Pt0.5Ni0.5 is the most thermodynamically stable. The Pt0.5Ni0.5 solid solution is highly ordered as it is composed mainly of two symmetrically inequivalent configurations of homogeneously distributed atoms. We have obtained the atomic projections of the electronic density of states and band structure, showing that the Pt0.5Ni0.5 alloy has metallic character. The suitable electronic properties of the thermodynamically stable Pt0.5Ni0.5 solid solution shows promise as a sustainable catalyst for future regenerative fuel cells
    corecore