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Este trabajo se centra en la estructura financiera de las empresas cuyas actividades pertenecen a la industria manufacturera y realizan su actividad en España. El objetivo es analizar la influencia de los factores que determinan las decisiones sobre el endeudamiento de las empresas manufactureras españolas, obteniendo como resultado que la rentabilidad, la liquidez, el tamaño, la tangibilidad de los activos empresariales, la industria y el riesgo operativo tienen una influencia significativa sobre el endeudamiento. Estos resultados se alcanzan a partir de una muestra de 4350 empresas entre los ejercicios económicos 2007 a 2017 y se lleva a cabo un análisis empírico, primeramente, univariante de cada una de las variables sobre el endeudamiento y, seguidamente, a través de un análisis de regresión lineal múltiple.

El presente trabajo fin de grado (TFG) está orientado al estudio de la identidad profesional de los docentes. Específicamente, centramos la mirada en las vivencias y experiencias que tenemos a lo largo de nuestro recorrido como aprendices. Esto influye directa o indirectamente en la persona que somos actualmente y, en consecuencia, en el profesional que somos y en cómo actuamos ante determinadas situaciones tanto dentro de nuestra aula como de nuestro centro escolar. en esta investigación se realiza un estudio de caso de cuatro maestras con el objetivo de analizar cómo influyen las experiencias y vivencias que han tenido en su infancia, sobre todo en el ámbito escolar, en la identidad docente actual que presentan cada una de ellas. El estudio de casos se lleva a cabo con un método de investigación cualitativa, concretamente la narrativa autobiográfica, la cual permite explorar la historia de vida y la trayectoria profesional de las maestras.

Reparación mediante soldadura de los álabes de la última etapa de la turbina de vapor de baja presión, así como un estudio previo de las partes, funcionamiento, material y daños producidos en el mismo, de la turbina de vapor.

Cellular senescence is an effective tumor-suppressive mechanism that causes a stable proliferative arrest in cells with potentially oncogenic alterations. Here, we have investigated the role of the p33ING1 tumor suppressor in the regulation of cellular senescence in human primary fibroblasts. We show that p33ING1 triggers a senescent phenotype in a p53-dependent fashion. Also, endogenous p33ING1 protein accumulates in chromatin in oncogene- senescent fibroblasts and its silencing by RNA interference impairs senescence triggered by oncogenes. Notably, the ability to induce senescence is lost in a mutant version of p33ING1 present in human tumors. Using specific point mutants, we further show that recognition of the chromatin mark H3K4me3 is essential for induction of senescence by p33ING1. Finally, we demonstrate that ING1-induced senescence is associated to a specific genetic signature with a strong representation of chemokine and cytokine signaling factors, which significantly overlaps with that of oncogene-induced senescence. In summary, our results identify ING1 as a critical epigenetic regulator of cellular senescence in human fibroblasts and highlight its role in control of gene expression in the context of this tumor-protective response. Key words: cellular senescence; chromatin; ING1; p53; histone marks., This work is supported by grants from the Spanish Ministry of Science and Innovation to IP (BFU2006-10882, SAF2009-09031) and FJB (CTQ2008-03115 ⁄ BQU).

Attosecond pump-probe experiments performed in small molecules have allowed tracking charge dynamics in the natural time scale of electron motion. That this is also possible in biologically relevant molecules is still a matter of debate, because the large number of available nuclear degrees of freedom might destroy the coherent charge dynamics induced by the attosecond pulse. Here we investigate extreme ultraviolet-induced charge dynamics in the amino acid tryptophan. We find that, although nuclear motion and nonadiabatic effects introduce some decoherence in the moving electron wave packet, these do not significantly modify the coherence induced by the attosecond pulse during the early stages of the dynamics, at least for molecules in their equilibrium geometry. Our conclusions are based on elaborate theoretical calculations and the experimental observation of sub-4 fs dynamics, which can only be reasonably assigned to electronic motion. Hence, attosecond pump-probe spectroscopy appears as a promising approach to induce and image charge dynamics in complex molecules.

A pump-probe experiment in the tetrafluoro-methane (CF4) molecule has been theoretically simulated, allowing one to access electron dynamics in its natural time scale: the attosecond. The chosen pump and probe pulses can be currently produced in most attosecond laboratories. In this scheme, CF4 is first ionized by an extreme UV (XUV) attosecond pulse and the charge dynamics induced in the corresponding cation is probed with a few-femtosecond visible light (VIS) pulse. We demonstrate that modulations in the calculated photoelectron spectra with the pump-probe delay reflect the dynamics of the XUV-induced electronic wave packet. In particular, from the analysis of these modulations in the interval of time delays where the pump and probe pulses do not overlap any more, one has access to the amplitudes and phases of the different components of the electronic wave packet generated by the attosecond pulse. These reflect a complex dynamics that basically consists of very fast charge fluctuations occurring all over the molecule without any preference for a particular molecular site. Keywords

Chemical reviews 117(16), 10760 - 10825 (2017). doi:10.1021/acs.chemrev.6b00453, Advances in attosecond science have led to a wealth of important discoveries in atomic, molecular, and solid-state physics and are progressively directing their footsteps toward problems of chemical interest. Relevant technical achievements in the generation and application of extreme-ultraviolet subfemtosecond pulses, the introduction of experimental techniques able to follow in time the electron dynamics in quantum systems, and the development of sophisticated theoretical methods for the interpretation of the outcomes of such experiments have raised a continuous growing interest in attosecond phenomena, as demonstrated by the vast literature on the subject. In this review, after introducing the physical mechanisms at the basis of attosecond pulse generation and attosecond technology and describing the theoretical tools that complement experimental research in this field, we will concentrate on the application of attosecond methods to the investigation of ultrafast processes in molecules, with emphasis in molecules of chemical and biological interest. The measurement and control of electronic motion in complex molecular structures is a formidable challenge, for both theory and experiment, but will indubitably have a tremendous impact on chemistry in the years to come., Published by ACS Publ., Washington, DC