Legal form and risk exposure in Spanish firms

It is well-known that the legal form adopted by a firm determines the type of legal responsibility borne by its owners in case of bankruptcy. In this paper we argue that a firm under a limited liability status should be characterized by a higher than average bankruptcy probability, which ultimately captures their risk exposure when output is affected by exogenous shocks. To test this prediction we extend Lee’s (1976) switching regressions model to a panel dataset of 1313 Spanish firms from 1990–1994, separating them into corporate and entrepreneurial forms (with/without limited liability, respectively). We consider both random effects and fixed effects panel data models, taking into account the potential endogeneity between risk exposure and the legal form choice. Our results confirm the hypothesis that firms under limited liability have significant higher risk exposure than firms under unlimited liability.Data and financial support provided by the Fundación Empresa Pública (Madrid)Publicad

Molybdenum-catalyzed enantioselective sulfoxidation controlled by a nonclassical hydrogen bond between coordinated chiral imidazolium-based dicarboxylate and peroxido ligands

Chiral alkyl aryl sulfoxides were obtained by molybdenum-catalyzed oxidation of alkyl aryl sulfides with hydrogen peroxide as oxidant in mild conditions with high yields and moderate enantioselectivities. The asymmetry is generated by the use of imidazolium-based dicarboxylic compounds, HLR. The in-situ-generated catalyst, a mixture of aqueous [Mo(O)(O2)2(H2O)n] with HLR as chirality inductors, in the presence of [PPh4]Br, was identified as the anionic binuclear complex [PPh4]{[Mo(O)(O2)2(H2O)]2( -LR)}, according to spectroscopic data and Density Functional Theory (DFT) calculations. A nonclassical hydrogen bond between one C–H bond of the alkyl R group of coordinated (LR)- and one oxygen atom of the peroxido ligand was identified as the interaction responsible for the asymmetry in the process. Additionally, the step that governs the enantioselectivity was theoretically analyzed by locating the transition states of the oxido-transfer to PhMeS of model complexes [Mo(O)(O2)2(H2O)( 1-O-LR)]- (R = H, iPr). The DDG6= is ca. 0 kcal mol-1 for R = H, racemic sulfoxide, meanwhile for chiral species the DDG6= of ca. 2 kcal mol-1 favors the formation of (R)-sulfoxide.Junta de Andalucía (Proyecto de Excelencia FQM-7079)Universidad de Sevilla (VI Plan Propio

Bidimensional Cross-Cloud Application Management with TOSCA and Brooklyn (summary)

The diversity in the way different cloud providers offer their services, give their SLAs, present their QoS, support different technologies, etc., complicates the portability and interoperability of cloud applications, and favors vendor lock-in. Standards like TOSCA, and tools supporting them, have come to help in the provider-independent description of cloud applications. After the variety of proposed cross-cloud application management tools, we propose going one step further in the unification of cloud services with a deployment tool in which IaaS and PaaS services are integrated into a unified interface. We provide support for applications whose components are to be deployed on different providers, indistinctly using IaaS and PaaS services. The TOSCA standard is used to define a portable model describing the topology of the cloud applications and the required resources in an agnostic, and providers- and resources-independent way. We include in this paper some highlights on our implementation on Apache Brooklyn and present a non-trivial example that illustrates our approach. Resumen del artículo publicado en: Jose Carrasco, Javier Cubo, Francisco Durán, Ernesto Pimentel. Bidimensional Cross-Cloud Application Management with TOSCA and Brooklyn, 9th IEEE International Conference on Cloud Computing (CLOUD 2016), San Francisco, (EEUU). IEEE Computer Society, 2016.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Sfrp1 promotes neuroinflammation through the modulation of ADAM10 proteolytic activity

Tesis Doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Biología Molecular. Fecha de lectura: 28-07-2017Esta tesis tiene embargado el acceso al texto completo hasta el 28-01-2019Growing evidence suggests the importance of immune response regulation for the maintenance of neural tissue homeostasis. Disruption of this homeostasis might be one of the causes contributing to the onset and development of neurological disorders. Inflammatory responses in the Central Nervous System (CNS) are mediated by astrocytes and microglial cells, which help to protect from pathogen invasion and respond to any kind of injury, in the attempt to repair the tissue. However, exacerbated inflammatory responses lead to pathogenic neurotoxicity and chronic neuroinflammation. The latter has been recognized as one of the drivers of diverse neurodegenerative and autoimmune diseases of the CNS. Previous work from our laboratory has demonstrated that Sfrp1 contributes to AD progression by inducing Aβ peptide generation. In the course of this study, we also observed that genetic inactivation of Sfrp1 was associated with particularly low levels of neuroinflammation. Because an increased Sfrp1 expression has been reported in several peripheral diseases associated with chronic inflammation, we hypothesised that Sfrp1 could directly contribute to the regulation of neuroinflammation. In this thesis, we have addressed this issue, providing evidence that support this hypothesis. Indeed, we show that Sfrp1 expression is upregulated in activated microglial cells and reactive astrocytes under diverse experimental pro-inflammatory conditions, including experimentally induced neuroinflammation, in mouse models for Alzheimer’s Disease (AD) and in Experimental Autoimmune Encephalomyelitis. On the contrary, genetic inactivation of Sfrp1 strongly reduces glial cells activation, ameliorating the pathological traits of the diseases. Sfrp1 overexpression is sufficient to induce an inflammatory response, activating glial cells and promoting the infiltration of immune cells, whereas preliminary studies indicate that antibody-mediated neutralization of Sfrp1 activity ameliorates AD pathological traits. From a mechanistic point of view, Sfrp1 seems to promote neuroinflammation by regulating ADAM10-mediated shedding of TREM2, CD200 and CX3CL1, proteins implicated in the activation of microglial cells. We thus propose that Sfrp1 is directly involved in modulating microglial activation during brain inflammation. We also suggest that Sfrp1 may represent a new therapeutic target to attenuate the exacerbated neuroinflammation present in numerous neurodegenerative diseases

Performance evaluation of space-time block coding using a realistic mobile radio channel

This paper presents a performance evaluation of space-time block coding (STBC) employing a realistic mobile radio channel model in macrocellular and urban environments. The bit error rate (BER) is computed by Monte-Carlo simulations in the down-link to evaluate its sensitivity to channel correlation. We consider a horizontal uniform linear array at the base station (BS) formed by up to four antenna elements, and one and two uncorrelated antenna elements at the mobile station (MS). The channel model includes the probability density function (pdf) of the azimuth and delay of the impinging waves and their expected power conditioned on the azimuth and delay. The statistical properties of the model are extracted from macrocellular measurements made in urban environments. Simulation results show that the use of STBC can provide significant gains with acceptable sensitivity to the channel correlation under realistic conditions.Peer ReviewedPostprint (published version

Analysis for the Knowledge Management application in maintenance engineering: Perception from maintenance technicians

[EN] Knowledge based on personal experience (tacit knowledge) acquired in problem solving actions and in maintenance actions is the fundamental basis for maintenance technicians in companies with great physical assets. Generally, there is no proper policy for managing strategic knowledge and its capture. In this article, through qualitative studies (grounded theory) and surveys conducted with technicians, the aim was to obtain the perception of the maintenance technicians' part of the companies, in order to establish the characteristics of the relation between the strategic aspects and the engineering aspects of industrial maintenance, regarding knowledge management, as well as the enablers and barriers to its application. The results show how a high level of tacit knowledge is used in this activity, which requires more time for new staff. The values obtained from this survey show that the knowledge recorded by the companies (explicit) is 51.25%, compared to the personal knowledge (tacit) of maintenance technicians regarding reliability and breakdowns. In operational/exploitational actions it is 43.90%, for energy efficiency actions it is 49.61%, and in maintenance actions (preventive, predictive, and corrective) the value is 68.78%. This shows the significant gap between the perception of recorded knowledge (explicit), and the knowledge that maintenance technicians have (tacit knowledge). All this can affect the companies, as part of the strategic knowledge is lost when a maintenance technician leaves the company.This work has been conducted within the framework of "Sistemas de mantenimiento industrial" project (Ref. 20140432) and the CONDAP project "Digital skills for workplace mentors in construction sector apprenticeships" funded by the European Commission within the Key Action 2: Cooperation for innovation and the exchange of good practices, reference number 2018-1-UK01KA202-048122Cárcel-Carrasco, J.; Cárcel-Carrasco, J. (2021). Analysis for the Knowledge Management application in maintenance engineering: Perception from maintenance technicians. Applied Sciences. 11 (2)(2):1-16. https://doi.org/10.3390/app11020703S11611 (2)

Inhomogeneous nucleation in quark hadron phase transition

The effect of subcritical hadron bubbles on a first-order quark-hadron phase transition is studied. These subcritical hadron bubbles are created due to thermal fluctuations, and can introduce a finite amount of phase mixing (quark phase mixed with hadron phase) even at and above the critical temperature. For reasonable choices of surface tension and correlation length, as obtained from the lattice QCD calculations, we show that the amount of phase mixing at the critical temperature remains below the percolation threshold. Thus, as the system cools below the critical temperature, the transition proceeds through the nucleation of critical-size hadron bubbles from a metastable quark-gluon phase (QGP), within an inhomogeneous background populated by an equilibrium distribution of subcritical hadron bubbles. The inhomogeneity of the medium results in a substantial reduction of the nucleation barrier for critical bubbles. Using the corrected nucleation barrier, we estimate the amount of supercooling for different parameters controlling the phase transition, and briefly discuss its implications to cosmology and heavy-ion collisions.Comment: LaTeX, 14 pages with 8 Postscript figures. Discussion added in introduction and conclusion, Fig. 8 added, few more references added, Typographical errors corrected. Version to appear in Phys. Rev.

A "quick look" at ultrafast ablation using fs-resolved phase-change microscopy

A pump-probe phase-change microscope with fs temporal resolution has been used to understand the transformation induced in the sample surface as a consequence of laser-matter interaction.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech