375 research outputs found
Local Anomalies, Local Equivariant Cohomology and the Variational Bicomplex
The locality conditions for the vanishing of local anomalies in field theory
are shown to admit a geometrical interpretation in terms of local equivariant
cohomology, thus providing a method to deal with the problem of locality in the
geometrical approaches to the study of local anomalies based on the
Atiyah-Singer index theorem. The local cohomology is shown to be related to the
cohomology of jet bundles by means of the variational bicomplex theory. Using
these results and the techniques for the computation of the cohomology of
invariant variational bicomplexes in terms of relative Gel'fand-Fuks cohomology
introduced in [6], we obtain necessary and sufficient conditions for the
cancellation of local gravitational and mixed anomalies.Comment: 36 pages. The paper is divided in two part
Equivariant characteristic classes in the bundle of connections
The characteristic forms in the bundle of connections of a principal bundle P
over M determine the characteristic classes of P for degree less or equal to
the dimension of M, and differential forms on the space of connections for
higher degree. The equivariant characteristic classes provide canonical
equivariant extensions of this forms, and so cohomology classes in the quotient
space of connections modulo gauge transformations. More generally, given a
closed differential form in M and a characteristic form, we obtain a cohomology
class in the space of connections modulo gauge transformations, and we show
that these classes coincide with some classes previously defined by Atiyah and
Singer.Comment: 16 page
Nuevos datos sobre la presencia de especies nuevas o poco conocidas de la ictiofauna marina de Galicia (II)
La bibliografía ictiológica de Galicia tiene
una larga historia que ha ido enriqueciéndose
con sucesivas aportaciones. Durante los últimos
años, una mayor atención científica y el estrecho
contacto con el sector pesquero, han permitido
mejorar el conocimiento de la ictiofauna marina
de Galicia, dando lugar al registro de especies
nuevas para aguas gallegas y europeas (Bañón,
2002; Bañón et al., 2007) y a la confirmación de
la presencia de especies citadas anteriormente.
En este trabajo se establecen seis nuevas citas
sobre la presencia de especies nuevas o poco
conocidas para las aguas de Galicia: Anjova
Pomatomus saltatrix (Linnaeus, 1766) (Pomatomatidae),
Jurelo negro Trachurus picturatus
(Bowdich, 1825) (Carangidae), Palometa blanca
Trachinotus ovatus (Linnaeus, 1758), pez volador
Cheilopogon heterurus. (Rafinesque, 1810),
Linterna negra Benthosema glaciale (Reinhardt,
1838) y Limanda noruega Phrynorhombus norvegicus
(Günther, 1862) (Scophthalmidae)
Enhanced gas sensing performance of TiO2 functionalized magneto-optical SPR sensors
9 páginas, 7 figurasPorous TiO2 thin films deposited by glancing angle deposition are used as sensing layers to monitor their sensing capabilities towards Volatile Organic Compounds both in a standard Surface Plasmon Resonance (SPR) sensor and in Magneto-Optical Surface Plasmon Resonance (MO-SPR) configuration in order to compare their sensing performances. Here our results on the enhanced sensing capability of these TiO2 functionalized MO-SPR sensors with Au/Co/Au transducers with respect to traditional SPR gas sensors are presented.This work has been funded by the European Commission (NMP3-SL-2008-214107-Nanomagma), the Spanish MICINN (CSD 2008-00023, MAT 2008-06765-C02-01/NAN, MAT2010-21228), CSIC (JAE fellowship for E. F.-V.) and Comunidad de Madrid (S2009 / MAT – 1726, S2009/TIC – 1476).Peer reviewe
A prospective evaluation of the predictive value of faecal calprotectin in quiescent Crohn’s disease
Background: The faecal calprotectin (FC) test is a non-invasive marker for gastrointestinal inflammation.
Aim: To determine whether higher FC levels in individuals with quiescent Crohn’s disease are associated with clinical relapse over the ensuing 12 months.<p></p>
Methods: A single centre prospective study was undertaken in Crohn's disease patients in clinical remission attending for routine review. The receiver operating characteristic (ROC) curve for the primary endpoint of clinical relapse by 12 months, based on FC at baseline, was calculated. Kaplan-Meier curves of time to relapse were based on the resulting optimal FC cutoff for predicting relapse.<p></p>
Results: Of 97 patients recruited, 92 were either followed up for 12 months without relapsing, or reached the primary endpoint within that period. Of these, 10 (11%) had relapsed by 12 months. The median FC was lower for non-relapsers, 96µg/g (IQR 39-237), than for relapsers, 414µg/g (IQR 259-590), (p=0.005). The area under the ROC curve to predict relapse using FC was 77.4%. An optimal cutoff FC value of 240µg/g to predict relapse of quiescent Crohn’s had sensitivity of 80.0% and specificity of 74.4%. Negative predictive value was 96.8% and positive predictive value was 27.6%. FC≥240μg/g was associated with likelihood of relapse 5.7 (95% CI 1.9-17.3) times higher within 2.3 years than lower values (p=0.002).<p></p>
Conclusions: In this prospective dataset, FC appears to be a useful, non-invasive tool to help identify quiescent Crohn’s disease patients at a low risk of relapse over the ensuing 12 months. FC of 240µg/g was the optimal cutoff in this cohort.<p></p>
From local monitoring to a broad‐scale viability assessment: a case study for the Bonelli's Eagle in western Europe
Population viability analysis (PVA) has become a basic tool of current conservation practice. However, if not accounted for properly, the uncertainties inherent to PVA predictions can decrease the reliability of this type of analysis. In the present study, we performed a PVA of the whole western European population (France, Portugal, and Spain) of the endangered Bonelli's Eagle (Aquila fasciata), in which we thoroughly explored the consequences of uncertainty in population processes and parameters on PVA predictions. First, we estimated key vital rates (survival, fertility, recruitment, and dispersal rates) using monitoring, ringing, and bibliographic data from the period 1990-2009 from 12 populations found throughout the studied geographic range. Second, we evaluated the uncertainty about model structure (i.e., the assumed processes that govern individual fates and population dynamics) by comparing the observed growth rates of the studied populations with model predictions for the same period. Third, using the model structures suggested in the previous step, we assessed the viability of both the local populations and the overall population. Finally, we analyzed the effects of model and parameter uncertainty on PVA predictions. Our results strongly support the idea that all local populations in western Europe belong to a single, spatially structured population operating as a source-sink system, whereby the populations in the south of the Iberian Peninsula act as sources and, thanks to dispersal, sustain all other local populations, which would otherwise decline. Predictions regarding population dynamics varied considerably, and models assuming more constrained dispersal predicted more pessimistic population trends than models assuming greater dispersal. Model predictions accounting for parameter uncertainty revealed a marked increase in the risk of population declines over the next 50 years. Sensitivity analyses indicated that adult and pre‐adult survival are the chief vital rates regulating these populations, and thus, the conservation efforts aimed at improving these survival rates should be strengthened in order to guarantee the long‐term viability of the European populations of this endangered species. Overall, the study provides a framework for the implementation of multi‐site PVAs and highlights the importance of dispersal processes in shaping the population dynamics of long‐lived birds distributed across heterogeneous landscapes
Galician consensus on management of cardiotoxicity in breast cancer: risk factors, prevention, and early intervention
This Galician consensus statement is a joint oncologists/cardiologists initiative indented to establish basic recommendations on how to prevent and to manage the cardiotoxicity in breast cancer with the aim of ensuring an optimal cardiovascular care of these patients. A clinical screening of the patients before treatment is recommended to stratify them into a determined risk group based on their intrinsic cardiovascular risk factors and those extrinsic arose from breast cancer therapy, thereby providing individualized preventive and monitoring measures. Suitable initial and ongoing assessments for patients with low and moderate/high risk and planned treatment with anthracyclines and trastuzumab are given; also, measures aimed at preventing and correcting any modifiable risk factor are pointed out .TEVA Farma Españ
Farmers’ reasoning behind the uptake of agroforestry practices: evidence from multiple case-studies across Europe
Potential benefits and costs of agroforestry practices have been analysed by experts, but few studies have captured farmers’ perspectives on why agroforestry might be adopted on a European scale. This study provides answers to this question, through an analysis of 183 farmer interviews in 14 case study systems in eight European countries. The study systems included high natural and cultural value agroforestry systems, silvoarable systems, high value tree systems, and silvopasture systems, as well as systems where no agroforestry practices were occurring. A mixed method approach combining quantitative and qualitative approaches was taken throughout the interviews. Narrative thematic data analysis was performed. Data collection proceeded until no new themes emerged. Within a given case study, i.e. the different systems in different European regions, this sampling was performed both for farmers who practice agroforestry and farmers who did not. Results point to a great diversity of agroforestry practices, although many of the farmers are not aware of the term or concept of agroforestry, despite implementing the practice in their own farms. While only a few farmers mentioned eligibility for direct payments in the CAP as the main reason to remove trees from their land, to avoid the reduction of the funded area, the tradition in the family or the region, learning from others, and increasing the diversification of products play the most important role in adopting or not agroforestry systems
Identificación de los Indicadores de seguimiento de las acciones de conservación. Acción A1 “Diagnosis, Análisis territorial e Identificación de Indicadores"
Las acciones de conservación de LIFE FLUVIAL precisan de una evaluación periódica
de sus repercusiones sobre el hábitat 91E0* y el hábitat 9230 (los dos hábitats objetivo
del proyecto). Cada socio en sus territorios debe llevar a cabo un seguimiento con motivo
de la acción D1 que permita evaluar la efectividad de las actuaciones de restauración
(acciones C) y realizar una toma de decisiones de acuerdo a los resultados de dicho
monitoreo, que pueda incluir cambios en las actuaciones previstas o la ejecución de
nuevas medidas.
En consecuencia, en el presente documento se establecen los indicadores de
seguimiento a emplear en la acción D1 de LIFE FLUVIAL, así como la metodología para su
aplicación. Los objetivos del seguimiento son:
A. Vigilar la evolución del proceso de restauración
B. Controlar los cambios que se produzcan
C. Detectar y corregir la aparición de efectos indeseables
D. Favorecer los procesos que se entiendan beneficiosos para recuperar la
naturalidad y biodiversidad del lugar.
En todo caso, hay que tener en cuenta que la duración del proyecto se queda corta
para poder abarcar todo el proceso de recuperación de la cubierta vegetal propiciado por
las acciones de conservación, de modo que, probablemente, los resultados del
seguimiento relativos a algunos parámetros no presentarán valores especialmente
significativos, debiendo interpretarse entonces como tendencias de la evolución de los
hábitats objetivo en los enclaves de actuación.info:eu-repo/semantics/publishedVersio
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