594 research outputs found

    Surface movement and cascade processes on debris cones in temperate high mountain (Picos de Europa, northern Spain)

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    Producción CientíficaDebris talus is a very common landform in the temperate high mountain, so much so that it is the most representative of the periglacial and nival processes. This work studies debris cones in the Picos de Europa, an Atlantic mountain range in the north of the Iberian Peninsula. A detailed geomorphological map was prepared, fieldwork was carried out on the debris cone surface, the ground and air thermal regime was analyzed, and a five-year Terrestrial Laser Scan survey carried out. Annual volume changes on the surface of the debris cones were detected and related to active processes and sediment transfer. Two different behaviors were observed in each cone. Cone A is linear, with equilibrium between accumulation and sediment transfer, while Cone B is concave-convex denoting accumulation processes in the upper part deriving from the greater frequency of snow avalanches. Changes in morphology surpass 50 cm/year with most of the activity taking place in the highest and lowest areas. The presence and action of the ice on the debris slope are moderate or non-existent and freeze-thaw processes are only active on the walls at over 2000 m a.s.l. The main processes on debris cones are debris flow and creep related to snowcover, but sediment transfer on the slopes involves high intensity-low frequency (debris flow, avalanches) and high frequency-low intensity processes (creep, shift, solifluction and wasting).Ministerio de Economía, Industria y Competitividad - Fondo Europeo de Desarrollo Regional (project CGL2015-68144-R)Junta de Extremadura - Fondo Europeo de Desarrollo Regional (project GR10071

    The role of GPR techniques in determining ice cave properties: Peña Castil ice cave, Picos de Europa

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    Producción CientíficaThe structure and ice content of ice caves are poorly understood. Ground penetrating radar (GPR) can provide useful insights but has only rarely been applied to ice caves. This paper interprets GPR images (radargrams) in terms of internal structure, stratification, compaction, thickness and volume of the ice block in the Peña Castil ice cave (Central Massif of Picos de Europa, northern Spain), providing the endokarst geometry of the ice cave in GPR data reflections. Eight radargrams were obtained by applying a shielded ground‐coupled antenna with a nominal frequency of 400 MHz. Although the radargrams do not depict the ice–basal bedrock interface, they suggest that the ice block is at least 54 m deep and similarly thick. Some curved reflection signatures suggest a potential vertical displacement in the block of ice, and thus certain dynamics in the ice body. Other images show numerous interbedded clasts and thin sediment layers imaged as banded reflections. In this particular cave a direct visual inspection of the ice stratigraphy is a difficult task but GPR provides clear reflectivity patterns of some of its internal features, making GPR a suitable instrument for this and future studies to achieve a better and broader understanding of the internal behavior of ice caves.Ministerio de Economía, Industria y Competitividad (project CGL2015-68144-R)Ministerio de Agricultura y Pesca, Alimentación y Medio Ambiente (project OAPN-053/2010

    Functionalization and Characterization of Magnetic Nanoparticles for the Detection of Ferritin Accumulation in Alzheimer's Disease

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    Early diagnosis in Alzheimer's disease (AD), prior to the appearance of marked clinical symptoms, is critical to prevent irreversible neuronal damage and neural malfunction that lead to dementia and death. Therefore, there is an urgent need to generate new contrast agents which reveal by a noninvasive method the presence of some of the pathological signs of AD. In the present study, we demonstrate for the first time a new nanoconjugate composed of magnetic nanoparticles bound to an antiferritin antibody, which has been developed based on the existence of iron deposits and high levels of the ferritin protein present in areas with a high accumulation of amyloid plaques (particularly the subiculum in the hippocampal area) in the brain of a transgenic mouse model with five familial AD mutations. Both in vitro and after intravenous injection, functionalized magnetic nanoparticles were able to recognize and bind specifically to the ferritin protein accumulated in the subiculum area of the AD transgenic mice.Fil: Fernández Cabada, Tamara. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Politécnica de Madrid; EspañaFil: Martínez Serrano, Alberto. Consejo Superior de Investigaciones Científicas; España. Universidad Autónoma de Madrid; EspañaFil: Cussó, Lorena. Instituto de Investigacion Sanitaria Gregorio Marañón; España. Universidad Carlos III de Madrid; España. Centro de Investigación Biomédica en Red de Salud Mental; EspañaFil: Desco, Manuel. Instituto de Investigacion Sanitaria Gregorio Marañón; España. Centro de Investigación Biomédica en Red de Salud Mental; España. Universidad Carlos III de Madrid; EspañaFil: Ramos Gómez, Milagros. Universidad Politécnica de Madrid; Españ

    Operators whose adjoints are quasi p-nuclear

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    For p ≥ 1, a set K in a Banach space X is said to be relatively p-compact if there exists a p-summable sequence (xn) in X with K ⊆{Pn αnxn : (αn) ∈ B`p0}. We prove that an operator T : X → Y is p-compact (i.e., T maps bounded sets to relatively p-compact sets) iff T∗ is quasi p-nuclear. Further, we characterize p-summing operators as those operators whose adjoints map relatively compact sets to relatively p-compact sets

    Some properties and applications of equicompact sets of operators

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    Let X and Y be Banach spaces. A subset M of K(X,Y ) (the vector space of all compact operators from X into Y endowed with the operator norm) is said to be equicompact if every bounded sequence (xn) in X has a subsequence (xk(n))n such that (Txk(n))n is uniformly convergent for T ∈ M. We study the relationship between this concept and the notion of uniformly completely continuous set and give some applications. Among other results, we obtain a generalization of the classical Ascoli theorem and a compactness criterion in Mc(F,X), the Banach space of all (finitely additive) vector measures (with compact range) from a field F of sets into X endowed with the semivariation norm

    The Effect of Corporate Social Responsibility on Earnings Management: Bibliometric Review

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    © 2021 by the authors. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/ 4.0/). This document is the Published version of a Published Work that appeared in final form in International Journal of Financial Studies. To access the final edited and published work see https://doi.org/10.3390/ijfs9040068This review aims to study the knowledge development and research dissemination on the influence of Corporate Social Responsibility (CSR) on earnings management through a social network approach using a bibliometric review. A systematic bibliometric review was carried out on 329 papers obtained from the Clarivate Analytics Web of Science (WoS) Core Collection database. The data were analyzed by year, journal, author, institution, country, affiliation, subject area and term analysis. The results reveal the growing interest of researchers in studying the impact of CSR. Although the USA and China dominate publication production, there are a large number of authors from more than 50 countries around the world. The results also show that being prolific does not imply being influential in this area. The keyword patterns showed some interesting potential areas of study on this topic. The findings of this paper provide insight to the research on the analysis of the influence of CSR on earnings management. The most important findings consist of a number of gaps in the literature, such as gender diversity, voluntary disclosure of information and existence of an audit committee, among others, that allow for future fields of research to improve the analysis of the influence of CSR in EM. This research should also prove helpful to managers, owners and auditors. This is the first bibliometric review developed on this topic and it can be extrapolated to any place in the world

    Mapping the potential distribution of frozen ground in Tucarroya (Monte Perdido Massif, the Pyrenees)

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    Producción CientíficaEste trabajo describe la metodología utilizada para cartografiar los suelos potencialmente helados en el valle de Tucarroya, en el Parque Nacional de Ordesa. Para cartografiar las formas asociadas a la presencia de hielo se combinó trabajo de campo, datos térmicos procedentes de sensores automáticos de temperatura del suelo y mediciones de la base del manto de nieve (BTS), así como variables predictivas obtenidas de un Modelo Digital de Elevaciones (MDE). La cartografía diferencia cuatro ambientes, suelo no congelado con actividad de la helada, suelos helados estacionales, permafrost posible y permafrost probable. El mapa revela una extensión del permafrost muy limitada, con escasez de formas asociadas. Solo se ha detectado por encima de los 2700 m de altitud en ambientes topográficos favorables, pendientessuaves y protegidos de la radiación solar. Los suelos helados estacionales son los ambientes más comunes y se desarrollan por encima de los 2500 m s.n.m., mientras los suelos no congelados,pero con heladas solo están presentes entre los 2570 y los 2750 m de altitud en laderas que reciben elevada radiación solarMinisterio de Economía, Industria y Competitividad - Fondo Europeo de Desarrollo Regional (projects CGL2015-68144-R / CGL2017-82216-R)Geoparque de Sobrarbe (project R- ADM15/57

    Los toros de mi tierra : siluetas de ganaderos e historiales de las ganaderías salamanquinas

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    Copia digital. Valladolid : Junta de Castilla y León. Consejería de Cultura y Turismo, 2009-201

    Geomatic methods applied to the change study of the la Paúl Rock Glacier, Spanish Pyrenees

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    Producción CientíficaRock glaciers are one of the most important features of the mountain permafrost in the Pyrenees. La Paúl is an active rock glacier located in the north face of the Posets massif in the La Paúl glacier cirque (Spanish Pyrenees). This study presents the preliminary results of the La Paúl rock glacier monitoring works carried out through two geomatic technologies since 2013: Global Navigation Satellite System (GNSS) receivers and Terrestrial Laser Scanning (TLS) devices. Displacements measured on the rock glacier surface have demonstrated both the activity of the rock glacier and the utility of this equipment for the rock glaciers dynamic analysis. The glacier has exhibited the fastest displacements on its west side (over 35 cm yr-1), affected by the Little Ice Age, and frontal area (over 25 cm yr-1). As an indicator of permafrost in marginal environments and its peculiar morphology, La Paúl rock glacier encourages a more prolonged study and to the application of more geomatic techniques for its detailed analysis.Ministerio de Economía, Industria y Competitividad - Fondo Europeo de Desarrollo Regional (project CGL2015-68144-R)Junta de Extremadura - Fondo Europeo de Desarrollo Regional (project GR10071

    Electrospinning for Drug Delivery Systems: Drug Incorporation Techniques

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    Electrospinning is a very versatile techniqueused for many purposes, such as tissue engineering, textiles, air and water treatment filter, solar cells, and drug delivery systems, among others. This method is cheap, easy to handle, reproducible when ambient parameters are controlled, and can be used for many formulations. The objective of this review is to enlist and emphasize the advantages and disadvantages of different methods for incorporating therapeutic drugs in a drug delivery system with electrospinning. The importance of the research to create new and innovative drug carriers is high, because of their efficiency of transporting the bioactive agent to the target zone, avoiding secondary effects in the body. Nanofibers and nanoparticles have become an important strategy in pharmacology due to their physicochemical and biocompatible properties useful for this purpose. Among the techniques compared are blending coaxial, emulsion and surface modification electrospinning, followed by electrospray and coaxial electrospray. The present review concludes that every technique has advantages and disadvantages and, not all drugs can be loaded with any method, the strategy used will depend on the drug’s physicochemical properties, target zone, polymeric characteristics, and required drug release rate. This chapter will serve as a starting point for when to choose one of the drug incorporation techniques mentioned
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