Search results for "CEO"

Tunable radical scavenging activity of carbonaceous structures and their anti-oxidant behaviour in polymer based nanocomposites

2017

Introduction: Carbon nanotubes (CNTs), due to their electronic properties, show radical scavenging activity toward the radical formed during the degradation processes of polymeric materials. In this work, we propose a novel strategy to control the CNTs anti-oxidant features through the application of an ultrasound treatment (us). Materials and Methods: Ultra high molecular weight polyethylene (UHMWPE); multi-walled carbon nanotubes (CNTs); CNTs have been sonicated at room temperature for different time intervals. Nanocomposites have been prepared though hot compaction and fully characterized. Results: The content of CNTs structural defects, evaluated through Raman-spectroscopy, increases wi…

Adenoma sebáceo de la glándula parótida

2006

Los tumores de las glándulas salivales constituyen un área importante de la patología oral y maxilofacial. La mayor parte de las neoplasias glandulares salivales son benignas, representando las malignas entre el 15 y el 32% del total. La localización más común de estas entidades es la glándula parótida, en la que asientan hasta el 80% de todos los casos. En este artículo se presenta un caso de adenoma sebáceo salival, de localización parotídea. El tumor, formado por células epiteliales que tapizan conductos, exhibe amplias áreas de diferenciación sebácea y zonas con metaplasia oncocítica. El patrón histológico es predominantemente quístico, observándose cavidades rellenas con material sebác…

Kinetic characterization of mitochondrial complex I inhibitors using annonaceous acetogenins

1999

The NADH:ubiquinone oxidoreductase (complex I) of the mitochondrial respiratory chain is by far the largest and most complicated of the proton-translocating enzymes involved in the oxidative phosphorylation. Many clues regarding the electron pathways from matrix NADH to membrane ubiquinone and the links of this process with the translocation of protons are highly controversial. Different types of inhibitors become valuable tools to dissect the electron and proton pathways of this complex enzyme. Therefore, further knowledge of the mode of action of complex I inhibitors is needed to understand the underlying mechanism of energy conservation. This study presents for the first time a detailed …

Evoluzione degli strumenti di supporto alla decisione per la valutazione ambientale territoriale

2009

Electronic and optical properties of CeO 2 from first principles calculations

2016

International audience; First-principles calculations of the electronic structure of CeO2 nanoparticles (NPs) were performed to investigate published experimental data obtained by different spectroscopies. The main features of the valence and conduction bands have been analyzed from the total and partial density of states. Several functionals were applied to interpret and quantify the optical properties, including the dielectric function, extinction coefficient and refractive index. It is found that the on-site hybrid functional B3PW91 modelled most suitably the band gap region of CeO2 NPs and consequently gave a more accurate band gap value. It also agreed very well with the experimental v…

Corporate social responsibility and managerial compensation: further evidence from spanish listed companies

2021

Ongoing regulatory efforts aim to link managerial compensation with a firm’s performance. However, little is known about whether and how Corporate Social Responsibility (CSR) goals are considered in the design of the managerial compensation scheme. This paper addresses this research question by analyzing a sample of Spanish listed firms for the period spanning 2013–2018. The outcomes of the regressions suggest that there is a positive relationship between CSR and the managerial compensation, but this relationship is significant only with lower levels of CSR. The study also reveals that CSR is positively associated with the proportion of equity-based compensation and, therefore, negatively a…

Evolution of neodymium isotopic signature of seawater during the Late Cretaceous: implications for intermediate and deep circulation.

2016

20 pages; International audience; Neodymium isotopic compositions (εNd) have been largely used for the last fifty years as a tracer of past ocean circulation, and more intensively during the last decade to investigate ocean circulation during the Cretaceous period. Despite a growing set of data, circulation patterns still remain unclear during this period. In particular, the identification of the deep-water masses and their spatial extension within the different oceanic basins are poorly constrained. In this study we present new deep-water εNd data inferred from the Nd isotope composition of fish remains and Fe–Mn oxyhydroxide coatings on foraminifera tests, along with new εNd data of resid…

Revisión de la sección del yacimiento del Mas de la Chimenea Alta (Formación Arcillas de Morella, Castellón) y significado en el contexto paleoambien…

2012

Desde los primeros estudios estratigráficos y paleontológicos, que datan de principios del siglo XX, la Fm Morella se ha caracterizado por su coloración rojiza y su contenido fósil. La mayor parte de sus depósitos se han interpretado como continentales, aunque con intercalaciones locales de materiales marinos. En esta unidad se da la paradoja de que muchos de los lugares descritos con fauna de vertebrados continentales se encuentran en depósitos interpretados como ambientes marinos poco profundos y de transición. La sección del Mas de la Chimenea Alta es un ejemplo. Ésta contiene yacimientos con fósiles de vertebrados que son claramente alóctonos, pero también otros, con icnitas que permite…

Fossil echinoid (Echinoidea, Echinodermata) diversity of the Early Cretaceous (Hauterivian) in the Paris Basin (France).

2013

11 pages; International audience; This dataset inventories occurrence records of fossil echinoid specimens collected in the Calcaires à Spatangues Formation (CSF) that crops out in the southeast of the Paris Basin (France), and is dated from the Acanthodiscus radiatus chronozone (ca. 132 Ma, early Hauterivian, Early Cretaceous). Fossil richness and abundance of the CSF has attracted the attention of palaeontologists since the middle of the nineteenth century. This dataset compiles occurrence data (referenced by locality names and geographic coordinates with decimal numbers) of fossil echinoids both collated from the literature published over a century and a half, and completed by data from …

The significance of dropstones in a tropical lacustrine setting, eastern Cameros Basin (Late Jurassic–Early Cretaceous, Spain)

2004

International audience; Outsized clasts (mainly white quartzite pebbles) are found in carbonate deposits of the Enciso Group exposed on the northern border of the Cameros rift basin (Late Jurassic – Early Cretaceous, northern Spain). In the Arnedillo section, all the stones are enclosed in micrite, which was assumed deposited in littoral to open lacustrine environments, with minor inputs of deltaic sandstones. The clasts are found in fine-grained lacustrine sediments either as isolated stones or as loosely packed elongated clusters occasionally associated with quartz sands and gravels. The mean size of the clasts is 40 mm (range: 3 – 100 mm); they are polished, well-rounded, and lack any fa…