561 research outputs found

    Effect of asymmetry of the radio source distribution on the apparent proper motion kinematic analysis

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    A new list of physical characteristics of 4261 astrometric radio sources, including all 717 ICRF-Ext.2 sources has been compiled. Comparison of our data of optical characteristics with the official International Earth Rotation and Reference Systems Service (IERS) list showed significant discrepancies for about half of 667 common sources. We also found that asymmetry in the radio sources distribution between hemispheres could cause significant correlation between the vector spherical harmonics, especially if the case of sparse distribution of the sources with high redshift. We identified radio sources having many-year observation history and lack redshift. This sources should be urgently observed at large optical telescopes. The list of optical characteristics created in this paper is recommended for use as a supplement material for the next International Celestial Reference Frame (ICRF) realization. It can be also effectively used for cosmological studies and planning of observing programs both in radio and optics.Comment: 9 page

    Large-scale determinants of diversity across Spanish forest habitats: accounting for model uncertainty in compositional and structural indicators

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    An integral understanding of forest biodiversity requires the exploration of the many aspects it comprises and of the numerous potential determinants of their distribution. The landscape ecological approach provides a necessary complement to conventional local studies that focus on individual plots or forest ownerships. However, most previous landscape studies used equally-sized cells as units of analysis to identify the factors affecting forest biodiversity distribution. Stratification of the analysis by habitats with a relatively homogeneous forest composition might be more adequate to capture the underlying patterns associated to the formation and development of a particular ensemble of interacting forest species. Here we used a landscape perspective in order to improve our understanding on the influence of large-scale explanatory factors on forest biodiversity indicators in Spanish habitats, covering a wide latitudinal and altitudinal range. We considered six forest biodiversity indicators estimated from more than 30,000 field plots in the Spanish national forest inventory, distributed in 213 forest habitats over 16 Spanish provinces. We explored biodiversity response to various environmental (climate and topography) and landscape configuration (fragmentation and shape complexity) variables through multiple linear regression models (built and assessed through the Akaike Information Criterion). In particular, we took into account the inherent model uncertainty when dealing with a complex and large set of variables, and considered different plausible models and their probability of being the best candidate for the observed data. Our results showed that compositional indicators (species richness and diversity) were mostly explained by environmental factors. Models for structural indicators (standing deadwood and stand complexity) had the worst fits and selection uncertainties, but did show significant associations with some configuration metrics. In general, biodiversity increased in habitats covering wider topographic ranges and comprising forest patches with more complex shapes. Patterns in other relationships varied between indicators (e.g. species richness vs. diversity), or even were opposed (trees vs. shrubs). Our study (1) allowed deepening the understanding of biodiversity patterns in a large set of Spanish forest habitats and (2) highlighted the increasing complexity of identifying common landscape conditions favouring forest biodiversity as the range of analysed biodiversity aspects is widened beyond the more commonly assessed species richness indicators.This work has received financial support from the Ministerio de Ciencia e Innovación (Spain) and FEDER funds through the IBEPFOR (CGL2006- 00312/BOS) project. The NFI data were supplied by the Ministerio de Medio Ambiente y Medio Rural y Marino, Spain)

    Comparison of micrometeorological techinques for estimating ammonia emission from covered slurry storage and land spreading of cattle slurry

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    The micrometeorological mass-balance integrated horizontal flux (IHF) technique has been commonly employed for measuring ammonia (NH3) emissions inon-field experiments. However, the inverse-dispersion modeling technique, such as the backward Lagrangian stochastic (bLS) modeling approach, is currently highlighted as offering flexibility in plot design and requiring a minimum number of samplers (Ro et al., 2013). The objective of this study was to make a comparison between the bLS technique with the IHF technique for estimating NH3 emission from flexible bag storage and following landspreading of dairy cattle slurry. Moreover, considering that NH3 emission in storage could have been non uniform, the effect on bLS estimates of a single point and multiple downwind concentration measurements was tested, as proposed by Sanz et al. (2010)

    Pilot Testing and Psychometric Validation of the Nijmegen Professionalism Scale for Spanish Nursing

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    Background and purpose: Professional commitment is frequently used as a humanistic care indicator. Thus, it is important to design and validate a tool which is able to measure professional commitment of nurses in Spain. In this study we aimed to analyze the psychometric properties of the Nijmegen Professionalism Scale for Spanish (NPS-S) nursing in order to verify its validity and reliability. Methods: We undertook the pilot testing and psychometric validation of the NPS-S. A total sample of 249 nursing professionals from a variety of areas of expertise took part in this study. The STrengthening the Reporting of OBservational studies in Epidemiology (STROBE) Statement was used for reporting this research. Results: The NPS-S achieved a high degree of content validity, construct validity, internal consistency, temporal stability, and usability; this version is, thus, equivalent to the Nijmegen Professionalism Scale in its original version. Implications for practice: Based on the results obtained from the validation of this tool, it is possible to affirm that the NPS-S is an effective instrument for measuring professional commitment in this population. The NPS-S will evaluate and thus contribute to the promotion of professional commitment in Spanish nursing. Additionally, it will serve to establish correlations between professional commitment and other variables including quality of care and patient satisfaction. Future studies should analyze the evaluation capacity of this tool

    Invasive breast cancer in Argentine women: Association between risk and prognostic factors with antigens of a peptidic and carbohydrate nature

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    Objective: In breast cancer, several tumor markers have been identified. The marker most extensively associated with breast cancer is MUC1. The objective of the study was to analyze prognostic and risk factors in relation to tumor markers in order to clarify breast cancer biology. A total of 349 primary tumor samples and lymph nodes from breast cancer patients were studied. Risk and prognostic factors were considered. An immunohistochemical approach was applied and an extensive statistical analysis was performed, including frequency analysis and analysis of variance. Correlation among variables was performed with principal component analysis. Results: All the antigens showed an increased expression according to tumor size increment; moreover, sialyl Lewis x expression showed a significant increase in relation to disease stage, whereas Tn and TF presented a positive tendency. Vascular invasion was related to sialyl Lewis x expression and number of metastatic lymph nodes. Taking into account risk factors, when a patient had at least one child, Lewis antigens diminished their expression. In relation to breastfeeding, sialyl Lewis x expression diminished, although its apical expression increased. Conclusion: Associations between MUC1 and carbohydrate antigens and risk and prognostic factors show the complexity of the cellular biological behavior that these antigens modulate in breast cancer.Facultad de Ciencias Médica

    Invasive breast cancer in Argentine women: Association between risk and prognostic factors with antigens of a peptidic and carbohydrate nature

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    Objective: In breast cancer, several tumor markers have been identified. The marker most extensively associated with breast cancer is MUC1. The objective of the study was to analyze prognostic and risk factors in relation to tumor markers in order to clarify breast cancer biology. A total of 349 primary tumor samples and lymph nodes from breast cancer patients were studied. Risk and prognostic factors were considered. An immunohistochemical approach was applied and an extensive statistical analysis was performed, including frequency analysis and analysis of variance. Correlation among variables was performed with principal component analysis. Results: All the antigens showed an increased expression according to tumor size increment; moreover, sialyl Lewis x expression showed a significant increase in relation to disease stage, whereas Tn and TF presented a positive tendency. Vascular invasion was related to sialyl Lewis x expression and number of metastatic lymph nodes. Taking into account risk factors, when a patient had at least one child, Lewis antigens diminished their expression. In relation to breastfeeding, sialyl Lewis x expression diminished, although its apical expression increased. Conclusion: Associations between MUC1 and carbohydrate antigens and risk and prognostic factors show the complexity of the cellular biological behavior that these antigens modulate in breast cancer.Facultad de Ciencias Médica

    Ammonia and greenhouse gas emissions from an enriched cage laying hen facility

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    [EN] Ammonia, methane, nitrous oxide and carbon dioxide emissions were measured during a complete production cycle in an enriched cage laying hen facility under Oceanic climate conditions. Continuous monitoring of gas concentration, ventilation rate and environmental parameters were conducted from April 2012 to September 2013. The seasonal and diurnal pattern of gas emissions was analysed. Seasonality effect was found for NH3 emission, showing an average emission of 144.9 mg d 1 hen 1 and 90.3 mg d 1 hen 1 in summer and winter, respectively. On the contrary, diurnal pattern of NH3 emission did not differ between these seasons. For CO2, mean emission values did not show seasonality, although the diurnal pattern differed between winter and summer. Results obtained for CH4 and N2O emissions did not provide sufficient evidence to determine either seasonality or diurnal effect on these gases. An NH3 emission factor of 7% of total N in manure was defined for this system. These losses increased at higher ventilation rates and lower belt cleaning frequencies. Thus, NH3 mitigation strategies at housing level should consider both parameters. Further studies would be necessary to determine how these factors regulate NH3 emission at laying hen houses. © 2016 IAgrE. Published by Elsevier Ltd. All rights reservedThis work has been funded by BATFARM Interreg-Atlantic Area Project (2009-1/071) entitled "Evaluation of best available techniques to decrease air and water pollution in animal farms". Oier Alberdi holds a grant from the Ph.D. student's research program of the Department of Economic Development and Competitiveness of the Basque Government. The authors are especially grateful to Larrabe Oilotegia S.A.T. that facilitated productive data and access to the farm and to the engineering company Ingenieria Avicola S.L. for the detailed information on ventilation aspects of the installation.Alberdi, O.; Arriaga, H.; Calvet, S.; Estellés, F.; Merino, P. (2016). Ammonia and greenhouse gas emissions from an enriched cage laying hen facility. Biosystems Engineering. 144:1-12. doi:10.1016/j.biosystemseng.2016.01.009S11214

    Plot size matters: Toward comparable species richness estimates across plot-based inventories

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    To understand the state and trends in biodiversity beyond the scope of monitoring programs, biodiversity indicators must be comparable across inventories. Species richness (SR) is one of the most widely used biodiversity indicators. However, as SR increases with the size of the area sampled, inventories using different plot sizes are hardly comparable. This study aims at producing a methodological framework that enables SR comparisons across plot-based inventories with differing plot sizes. We used National Forest Inventory (NFI) data from Norway, Slovakia, Spain, and Switzerland to build sample-based rarefaction curves by randomly incrementally aggregating plots, representing the relationship between SR and sampled area. As aggregated plots can be far apart and subject to different environmental conditions, we estimated the amount of environmental heterogeneity (EH) introduced in the aggregation process. By correcting for this EH, we produced adjusted rarefaction curves mimicking the sampling of environmentally homogeneous forest stands, thus reducing the effect of plot size and enabling reliable SR comparisons between inventories. Models were built using the Conway–Maxell–Poisson distribution to account for the underdispersed SR data. Our method successfully corrected for the EH introduced during the aggregation process in all countries, with better performances in Norway and Switzerland. We further found that SR comparisons across countries based on the country-specific NFI plot sizes are misleading, and that our approach offers an opportunity to harmonize pan-European SR monitoring. Our method provides reliable and comparable SR estimates for inventories that use different plot sizes. Our approach can be applied to any plot-based inventory and count data other than SR, thus allowing a more comprehensive assessment of biodiversity across various scales and ecosystems.publishedVersio

    Modelización de un sistema territorial “urbano-rural” para la evaluación de su sostenibilidad. Aplicación a una zona representativa del País Vasco

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    El desarrollo de una base de conocimiento común y sólida que permita la máxima objetividad y transparencia en la evaluación de la sostenibilidad dentro del proceso de toma de decisiones, constituye uno de los pilares básicos para su implementación en el planeamiento estratégico y la gestión del territorio. La caracterización del sistema ecológico-ambiental, económico, social e institucional que es objeto de gestión constituye un paso clave en el conocimiento de la red de relaciones que subyace al funcionamiento del sistema y de las interacciones responsables de potenciales sinergias. La traducción de esta información en modelos conceptuales y matemáticos constituye una herramienta útil en el desarrollo de indicadores de sostenibilidad eficaces y relevantes, enfocados desde las necesidades de gestión. En este trabajo se presenta el modelo conceptual que define los componentes e interacciones de un sistema urbano-rural representativo del País Vasco, así como su marco de evaluación.One of the most important factors in introducing the concept of sustainability into strategic planning and territorial management is the development of a shared, solid knowledge base. This knowledge base should ensure maximum objectivity and transparency in sustainability assessment within the decision-making process. A description of the ecological-environmental, economic, social and institutional system that is to be managed is needed in order to develop knowledge about the network of relations that underlie the functioning of the system and the interactions that are responsible for potential synergies. The transformation of this information into conceptual and mathematical models is a useful tool for developing effective and relevant sustainability indicators that are oriented towards management needs. This paper presents a conceptual model that defines the components and interactions of a representative urban-rural system in the Basque Country. It also discusses the assessment frame for this model
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