2,695 research outputs found

    Streaky 3D Structures in the Boundary Layer

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    It has been recently shown [Choi, Nature, April 06 - Cossu, PRL, February 06] that 3D streaky structures in the boundary layer can remain laminar longer than the 2D Blasius °ow. The aim of this investigation is to study the possibility of promoting these 3D streaky structures via surface roughness, computing them and evaluat- ing the resulting stabilization using the Reduced Navier Stokes equations (RNS). The RNS are derived from Navier-Stokes making use of the fact that two very di®erent scales are present: one slow (streamwise direc- tion) and two short (spanwise and wall-normal direction). The RNS allows us to perform these 3D computations in a standard PC, without using CPU costly DNS simulations

    ActualizaciĂłn de la colecciĂłn de tipos del herbario MACB, II

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    CARRASCO, M. A. & MARTÍN-BLANCO, C. J. 2002. Actualización de la colección de Tipos del Herbario MACB. Bot. Complutensis, 26: 59-62. Se actualiza la Colección de Tipos del Herbario MACB, presentando los Typus de siete nombres. Señalamos la categoria de cada Tipo y los herbarios que tienen material tipo de los mismos taxones. Los nuevos Tipos son: 2 Holotypus, 4 Isotypus, 1 Isolectotypus y 2 Sintypus.CARRASCO, M. A. & MARTÍN-BLANCO, C. J. 2002. Update of the MACB type collection, II. Bot. Complutensis, 26: 59-62. In this paper the Type collection of the MACB Herbarium is update. We indicate the category of seven names (Holotypus, Isotypus Isolectotypus or Sintypus), as well as the herbariums with other type specimens of the same taxa. The new Typus are: 2 Holotypus, 4 Isotypus, 1 Isolectotypus and 2 Sintypus

    Computation of nonlinear streaky structures in boundary layer flow

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    In this work, the Reduced Navier Stokes (RNS) are numerically integrated, and used to calculate nonlinear finite amplitude streaks. These structures are interesting since they can have a stabilizing effect and delay the transition to the turbulent regime. RNS formulation is also used to compute the family of nonlinear intrinsic streaks that emerge from the leading edge in absence of any external perturbation. Finally, this formulation is generalized to include the possibility of having a curved bottom wal

    Antimicrobial resistance in patients with odontogenic infections : a systematic scoping review of prospective and experimental studies

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    Patients with odontogenic infections are commonly prescribed antimicrobials on an experiential base without knowing the precise microorganisms implicated. The aim of this systematic scoping review is to evaluate the prevalence and proportions of antimicr

    Identifying past social-ecological thresholds to understand long-term temporal dynamics in Spain

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    A thorough understanding of long-term temporal social-ecological dynamics at the national scale helps to explain the current condition of a country’s ecosystems and to support environmental policies to tackle future sustainability challenges. We aimed to develop a methodological approach to understand past long-term (1960-2010) social-ecological dynamics in Spain. First, we developed a methodical framework that allowed us to explore complex social-ecological dynamics among biodiversity, ecosystem services, human well-being, drivers of change, and institutional responses. Second, we compiled 21 long-term, national-scale indicators and analyzed their temporal relationships through a redundancy analysis. Third, we used a Bayesian change point analysis to detect evidence of past social-ecological thresholds and historical time periods. Our results revealed that Spain has passed through four socialecological thresholds that define five different time periods of nature and society relationships. Finally, we discussed how the proposed methodological approach helps to reinterpret national-level ecosystem indicators through a new conceptual lens to develop a more systems-based way of understanding long-term social-ecological patterns and dynamicsThis work was supported by the Biodiversity Foundation (http://www.fundacion-biodiversidad.es/) of the Spanish Ministry of Agriculture, Food and Environment. Partial financial support was also provided by the Ministry of Economy and Competitiveness of Spain (project CGL2014-53782-P: ECOGRADIENTES). The Spanish National Institute for Agriculture and Food Research and Technology (INIA) funded Marina García-Llorente as part of the European Social Fund. Blanca González García-Mon participated in this article as a “la Caixa” Banking Foundation scholar. The funders had no role in the study design, data collection and analysis, preparation of the report, or the decision to submit the study for publicatio

    The pitfall-trap of species conservation priority setting

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    This an accepted author's manuscript (AAM) version of an article published in Biodiversity and Conservation, 20 (2011): 663-68

    Conservation status of the world’s carnivorous mammals (order Carnivora)

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    CRUE-CSIC (Acuerdos Transformativos 2022)The conservation of carnivores (order Carnivora) can lead to the conservation of other species as well as entire ecosystems since they play an important ecosystemic role. However, their predatory behaviour has caused many of these species to experience marked population declines worldwide and they may therefore face greater anthropogenic threats than other animal groups. To examine the conservation status, population trends, distribution patterns, habitats and threats of all extant species belonging to this order (N=290), we collected data from the International Union for the Conservation of Nature's Red List. In addition, we calculated the Red List Index (RLI) to measure the change in extinction risk of species over time. Carnivores are more threatened than mammals in general (26.9% of endangered species vs. 22.7%) and have a signifcantly higher proportion of species with declining populations (48.3% vs. 31.9%). Eupleridae, Ursidae and Felidae families have the worst conservation status. Between the 1990s and 2000s, most families sufered a considerable decline in their RLI value, the most notable being Felidae. The greatest numbers of threatened carnivore species are found in forest, shrubland and grassland habitats. East and South Asia hold great numbers of carnivore species as well as the highest proportion of threatened and declining species. Hunting and trapping of terrestrial animals, along with habitat loss (caused by deforestation and agricultural expansion), pose the main threats to the Carnivora order. Our fndings indicate that, within mammals, the conservation of carnivores should be a priority, and conservation measures directed at this group should be undertaken or increased as a matter of urgency.Depto. de Biodiversidad, EcologĂ­a y EvoluciĂłnFac. de Ciencias BiolĂłgicasTRUEpu

    Role of floral strips and semi-natural habitats as enhancers of wild bee functional diversity in intensive agricultural landscapes

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    Los autores de la UAM pertenecen al Terrestrial Ecology Group, Department of EcologyInstalling patches of flowering plants is a commonly used strategy to enhance refuge and food resources for pollinators in intensive agricultural landscapes. Here, we evaluated how floral strips and semi-natural habitats impact the taxonomic and functional diversity of wild bees in intensively farmed sunflower fields. Pan traps were used to assess bee richness and functional diversity at 22 sampling sites (11 sites were positioned in sunflower fields with floral strips, and 11 control sites were adjacent to semi-natural habitats). Five sampling levels were established in each field, positioned at different distances from the flower strip or semi-natural habitat. Wild bee species richness and functional richness were significantly higher inside floral strips and semi-natural habitats compared to sunflower fields. Functional redundancy was significantly higher inside agricultural fields compared to inside floral strips and semi-natural habitats. Sunflower fields with floral strips had lower Rao values compared to sunflower fields adjacent to semi-natural habitats. The community-weighted mean (CWM) of intertegular distance (distance between where wings attach to body) of wild bees was significantly higher in sunflower fields adjacent to semi-natural habitats. In comparison, the CWM of wing length varied across sampling levels in sunflower fields with semi-natural habitats. Our results show it is essential to have semi-natural habitats within intensive agricultural landscapes to ensure the conservation of wild bee diversity, while the installation of floral strips offers a partial substitute to enhance wild bee diversity when semi-natural habitats are scarce or absentFinancial support was provided by the European Union FEDER INTERREG SUDOE Program (SOE1/P5/E0129). CPC was supported by the Estonian Ministry of Education and Research (PSG293) and the European Regional Development Fund (Centre of Excellence EcolChange

    Modeling at farm level: Positive Multi-Attribute Utility Programming

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    This article proposes a new mathematical programming model for the simulation of farmers’ decision-making. We have developed a model based on a multi-attribute utility approach that takes into consideration the most relevant attributes of farmers within a positive framework. This approach overcomes the limitations found in some mathematical models used in the literature to simulate farmers’ behavior. A five-step procedure is presented in order to elicit the utility function that reproduces farmers’ current decision-making. We illustrate this positive multi-attribute approach using a sample of farmers in an irrigated area in southern Spain, where our simulations demonstrate the accurateness of the model in reproducing actual farmers’ decision-making. We also find evidence that the model is able to explain the heterogeneous behavior of farmers within a homogeneous agricultural syste

    High resistance against clindamycin, metronidazole and amoxicillin in Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans isolates of periodontal disease

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    Objectives: To test the antimicrobial sensitivity of two periodontal pathogens to a panel of five orally administrable antibiotics in periodontal disease. Study design: A total of 69 isolates of Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis were processed using culture and biochemical tests. Selected colonies of A. actinomycetemcomitans and P. gingivalis were used to evaluate the antibacterial activity of clindamycin, metronidazole, amoxicillin, moxifloxacin and amoxicillin/clavulanic acid. Results: Susceptibility testing revealed a sensitivity of 100% of A. actinomycetemcomitans and P. gingivalis to moxifloxacin and amoxicillin/clavulanic acid but moderate susceptibilities were found for the rest of antibiotics agents evaluated. Conclusions: The widespread use of antibiotics is reflected in the level of resistance of A. actinomycetemcomitans and P. gingivalis in patients with periodontal infections. This suggests that antibiotic susceptibility testing is necessary to determine efficacy of antimicrobial agents. Clinical studies with antibiotics should take these differences into account
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