El comportamiento del gasto público en España durante la Segunda República, 1931-1935

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Hedge funds y riesgo sistémico : una primera aproximación

Artículo de revistaLa industria de hedge funds (HF) muestra un crecimiento importante desde el año 2000, tanto en número de fondos como en tamaño de activos gestionados. En dicho crecimiento juega un papel importante el aumento de la participación de los inversores institucionales, en especial de los fondos de hedge funds, que sirven de canalización a las inversiones minoristas. El tamaño de la industria aún es pequeño en comparación con la inversión colectiva tradicional, pero su peso en los mercados es elevado en muchas ocasiones debido al dinamismo de sus estrategias. Estas características han vuelto a plantear la cuestión del potencial de los HF para causar inestabilidad financiera. La gestión de riesgos realizada por los hedge funds y por las entidades bancarias que les proporcionan servicios financieros ha mejorado desde la crisis del Long Term Capital Management (LTCM) en 1998. No obstante, aún está lejos de ser satisfactoria. El potencial desestabilizador de los hedge funds provendría de las dificultades de realizar una gestión de riesgos adecuada para estrategias dinámicas por parte de los gestores de los fondos, de la concentración de posiciones por seguimiento de las mismas estrategias o de la dificultad de agregación de todas las exposiciones que tienen las entidades bancarias con los hedge funds

Riesgos en la compensación y liquidación transfronteriza de valores

Artículo de revistaSi, en un sentido amplio, el sistema de pagos se define como el conjunto de instituciones, instrumentos, reglas, procedimientos y medios técnicos que permiten intercambiar valor financiero entre dos partes de forma que se salden obligaciones, los sistemas de compensación y liquidación de valores entran plenamente en este concepto, circunscribiéndose su actividad a las obligaciones surgidas de la contratación en los mercados de valores. Por tanto, los sistemas de compensación y liquidación de valores constituyen uno de los principales componentes de la infraestructura financiera de un país y deben cumplir los requisitos de seguridad, solvencia y eficiencia exigibles a todas las instituciones que forman el sistema financiero. Las autoridades monetarias y financieras de los diferentes países tienen distintas aproximaciones a los sistemas de compensación y liquidación de valores. En algunos casos se limitan a fijar su regulación y supervisión, considerando que se trata de una actividad de naturaleza privada. Otros países establecen un régimen de concesión monopolista, al considerar que se trata de una actividad pública. Por último, pueden incluso llegar a ocuparse directamente de la administración y gestión de esta actividad, como sucede cuando los bancos centrales se encargan de la compensación y liquidación del mercado de deuda pública, en exclusiva o de forma complementaria a otros sistemas privados

MiFID : un nuevo marco de competencia para los mercados de valores

Artículo de revistaLa Directiva de Mercados en Instrumentos Financieros (MiFID) tiene como objetivo último contribuir a la creación de un mercado financiero europeo integrado, eficiente y competitivo. Para ello facilita la competencia entre los centros de negociación de valores al eliminar el principio de concentración en los mercados regulados, armonizar los requisitos y las condiciones operativas de mercados organizados con los de otros mecanismos alternativos de negociación (SMN) y reconocer la internalización como vía de contratación. Por otra parte la MiFID pretende evitar que la competencia suponga un deterioro a la protección que requieren los inversores minoritarios, que es fundamental para asegurar su confianza en los mercados. Para su logro, la Directiva regula de forma exhaustiva las obligaciones organizativas y de conducta que deben cumplir las empresas de inversión. Una de sus prescripciones más novedosas es el principio de mejor ejecución por el que las empresas se ven obligadas a establecer formalmente una política de actuación para conseguir los mejores resultados posibles para los clientes y, además, a estar dispuestas a demostrar su cumplimiento ante estos

Transcriptome analysis of perirenal fat from Spanish Assaf suckling lamb carcasses showing different levels of kidney knob and channel fat

[EN] Introduction: Suckling lamb meat is highly appreciated in European Mediterranean countries because of its mild flavor and soft texture. In suckling lamb carcasses, perirenal and pelvic fat depots account for a large fraction of carcass fat accumulation, and their proportions are used as an indicator of carcass quality. Material and Methods: This study aimed to characterize the genetic mechanisms that regulate fat deposition in suckling lambs by evaluating the transcriptomic differences between Spanish Assaf lambs with significantly different proportions of kidney knob and channel fat (KKCF) depots in their carcasses (4 High-KKCF lambs vs. 4 Low-KKCF lambs). Results: The analyzed fat tissue showed overall dominant expression of white adipose tissue gene markers, although due to the young age of the animals (17–36 days), the expression of some brown adipose tissue gene markers (e.g., UCP1, CIDEA) was still identified. The transcriptomic comparison between the High-KKCF and Low-KKCF groups revealed a total of 80 differentially expressed genes (DEGs). The enrichment analysis of the 49 DEGs with increased expression levels in the Low-KKCF lambs identified significant terms linked to the biosynthesis of lipids and thermogenesis, which may be related to the higher expression of the UCP1 gene in this group. In contrast, the enrichment analysis of the 31 DEGs with increased expression in the High-KKCF lambs highlighted angiogenesis as a key biological process supported by the higher expression of some genes, such as VEGF-A and THBS1, which encode a major angiogenic factor and a large adhesive extracellular matrix glycoprotein, respectively. Discussion: The increased expression of sestrins, which are negative regulators of the mTOR complex, suggests that the preadipocyte differentiation stage is being inhibited in the High-KKCF group in favor of adipose tissue expansion, in which vasculogenesis is an essential process. All of these results suggest that the fat depots of the High-KKCF animals are in a later stage of development than those of the Low-KKCF lambs. Further genomic studies based on larger sample sizes and complementary analyses, such as the identification of polymorphisms in the DEGs, should be designed to confirm these results and achieve a deeper understanding of the genetic mechanisms underlying fat deposition in suckling lambsSIThe research described here has been funded by the project EpiMilksheep (RTI2018-093535-B-100) funded by the Spanish Ministry of Science and Innovation. MA-G is funded by a predoctoral fellowship from the Junta de Castilla and León Government and the European Social Fun

Normative database for separate inner retinal layers thickness using spectral domain optical coherence tomography in Caucasian population

Purpose: Develop the first normative database of the thickness of every inner retinal layer in the macular area in a healthy, Caucasian population between 18 to 87 years old, using Spectralis Optical Coherence Tomography (OCT). Methods: On this transversal, observational study, 300 patients between 18 to 87 years old and without an ophthalmological condition were recruited. Macular OCT scans were performed on all patients (Spectralis OCT, Heidelberg Engineering). An axial length measurement, and keratometry were performed using an optical biometer. The volume and thickness of the different macular sectors of the inner retinal layers (retinal nerve fiber layer (RNFL), ganglion cells layer (CGL) and inner plexiform layer (IPL)) were analyzed with the Spectralis OCT segmentation software. An eye was randomly selected for each patient. Results: 297 patients (179 females and 118 males) were included in the study. The mean age was 56.07 years (range: 40.50-72). The multivariate analysis showed a positive correlation between the RNFL thickness and the axial length (p < 0.001). The mean central retinal thickness was 278.2 Mm (range: 266-291), the mean central RNFL thickness was 12.61 Mm (range: 11-14), the mean central CGL thickness was 17.63 Mm (range: 14-21) and the mean central IPL thickness was 22.02 Mm (range: 20-25). The multivariate analysis showed a negative correlation between age and CGL thickness and inner IPL thickness (p< 0.001). Conclusion: This study provides a normative database of the volume of each of the inner retinal layers on a Caucasian population

Evidence of a complex structure within the 2013 August 19 coronal mass ejection: Radial and longitudinal evolution in the inner heliosphere

Context. Late on 2013 August 19, a coronal mass ejection (CME) erupted from an active region located near the far-side central meridian from Earth’s perspective. The event and its accompanying shock were remotely observed by the STEREO-A, STEREO-B, and SOHO spacecraft. The interplanetary counterpart (ICME) was intercepted by MESSENGER near 0.3 au and by both STEREO-A and STEREO-B near 1 au, which were separated from each other by 78° in heliolongitude. Aims. The main objective of this study is to follow the radial and longitudinal evolution of the ICME throughout the inner heliosphere and to examine possible scenarios for the different magnetic flux-rope configuration observed on the solar disk and measured in situ at the locations of MESSENGER and STEREO-A, separated by 15° in heliolongitude, and at STEREO-B, which detected the ICME flank. Methods. Solar disk observations are used to estimate the “magnetic flux-rope type”, namely, the magnetic helicity, axis orientation, and axial magnetic field direction of the flux rope. The graduated cylindrical shell model is used to reconstruct the CME in the corona. The analysis of in situ data, specifically the plasma and magnetic field, is used to estimate the global interplanetary shock geometry and to derive the magnetic flux-rope type at different in situ locations, which is compared to the type estimated from solar disk observations. The elliptical cylindrical analytical model is used for the in situ magnetic flux-rope reconstruction. Results. Based on the CME geometry and on the spacecraft configuration, we find that the magnetic flux-rope structure detected at STEREO-B belongs to the same ICME detected at MESSENGER and STEREO-A. The opposite helicity deduced at STEREO-B might be due to that fact that it intercepted one of the legs of the structure far from the flux-rope axis, in contrast to STEREO-A and MESSENGER, which were crossing through the core of the magnetic flux rope. The different flux-rope orientations measured at MESSENGER and STEREO-A probably arise because the two spacecraft measure a curved, highly distorted, and rather complex magnetic flux-rope topology. The ICME may have suffered additional distortion in its evolution in the inner heliosphere, such as the west flank propagating faster than the east flank when arriving near 1 au. Conclusions. This work illustrates how a wide, curved, highly distorted, and rather complex CME showed different orientations as observed on the solar disk and measured in situ at 0.3 au and near 1 au. Furthermore, the work shows how the ambient conditions can significantly affect the expansion and propagation of the CME and ICME, introducing additional irregularities to the already asymmetric eruption. The study also manifests how these complex structures cannot be directly reconstructed with the currently available models and that multi-point analysis is of the utmost importance in such complex events.Agencia Estatal de Investigació

Characterization of mutant versions of the R-RAS2/TC21 GTPase found in tumors

The R-RAS2 GTP hydrolase (GTPase) (also known as TC21) has been traditionally considered quite similar to classical RAS proteins at the regulatory and signaling levels. Recently, a long-tail hotspot mutation targeting the R-RAS2/TC21 Gln72 residue (Q72L) was identified as a potent oncogenic driver. Additional point mutations were also found in other tumors at low frequencies. Despite this, little information is available regarding the transforming role of these mutant versions and their relevance for the tumorigenic properties of already-transformed cancer cells. Here, we report that many of the RRAS2 mutations found in human cancers are highly transforming when expressed in immortalized cell lines. Moreover, the expression of endogenous R-RAS2Q72L is important for maintaining optimal levels of PI3K and ERK activities as well as for the adhesion, invasiveness, proliferation, and mitochondrial respiration of ovarian and breast cancer cell lines. Endogenous R-RAS2Q72L also regulates gene expression programs linked to both cell adhesion and inflammatory/immune-related responses. Endogenous R-RAS2Q72L is also quite relevant for the in vivo tumorigenic activity of these cells. This dependency is observed even though these cancer cell lines bear concurrent gain-of-function mutations in genes encoding RAS signaling elements. Finally, we show that endogenous R-RAS2, unlike the case of classical RAS proteins, specifically localizes in focal adhesions. Collectively, these results indicate that gain-of-function mutations of R-RAS2/TC21 play roles in tumor initiation and maintenance that are not fully redundant with those regulated by classical RAS oncoproteins

Rifampicin and Its Derivative Rifampicin Quinone Reduce Microglial Inflammatory Responses and Neurodegeneration Induced In Vitro by α-Synuclein Fibrillary Aggregates

Abstract: Aggregated forms of the synaptic protein α‐synuclein (αS) have been proposed to operateas a molecular trigger for microglial inflammatory processes and neurodegeneration in Parkinson´sdisease. Here, we used brain microglial cell cultures activated by fibrillary forms of recombinanthuman αS to assess the anti‐inflammatory and neuroprotective activities of the antibiotic rifampicin(Rif) and its autoxidation product rifampicin quinone (RifQ). Pretreatments with Rif and RifQreduced the secretion of prototypical inflammatory cytokines (TNF‐, IL‐6) and the burst ofoxidative stress in microglial cells activated with αS fibrillary aggregates. Note, however, that RifQwas constantly more efficacious than its parent compound in reducing microglial activation. Wealso established that the suppressive effects of Rif and RifQ on cytokine release was probably dueto inhibition of both PI3K‐ and non‐PI3K‐dependent signaling events. The control of oxidative stressappeared, however, essentially dependent on PI3K inhibition. Of interest, we also showed that RifQwas more efficient than Rif in protecting neuronal cells from toxic factors secreted by microgliaactivated by αS fibrils. Overall, data with RifQ are promising enough to justify further studies toconfirm the potential of this compound as an anti‐parkinsionian drug.Fil: Acuña, Leonardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Patología Experimental. Universidad Nacional de Salta. Facultad de Ciencias de la Salud. Instituto de Patología Experimental; Argentina. Sorbonne University; Francia. Centre National de la Recherche Scientifique; FranciaFil: Hamadat, Sabah. Sorbonne University; FranciaFil: Corbalan, Natalia Soledad. Université Paris Est Créteil; Francia. Universidad Nacional de Tucuman. Instituto de Investigaciones En Medicina Molecular y Celular Aplicada del Bicentenario. - Gobierno de la Provincia de Tucuman. Ministerio de Salud. Sistema Provincial de Salud. Instituto de Investigaciones En Medicina Molecular y Celular Aplicada del Bicentenario. - Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet Noa Sur. Instituto de Investigaciones En Medicina Molecular y Celular Aplicada del Bicentenario.; ArgentinaFil: González Lizarraga, Maria Florencia. Universidad Nacional de Tucuman. Instituto de Investigaciones En Medicina Molecular y Celular Aplicada del Bicentenario. - Gobierno de la Provincia de Tucuman. Ministerio de Salud. Sistema Provincial de Salud. Instituto de Investigaciones En Medicina Molecular y Celular Aplicada del Bicentenario. - Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet Noa Sur. Instituto de Investigaciones En Medicina Molecular y Celular Aplicada del Bicentenario.; ArgentinaFil: Dos Santos Pereira, Mauricio. Sorbonne University; Francia. Centre National de la Recherche Scientifique; Francia. Universidade de Sao Paulo; BrasilFil: Rocca, Jérémy. Sorbonne University; Francia. Centre National de la Recherche Scientifique; FranciaFil: Sepúlveda Díaz, Julia. Sorbonne University; Francia. Centre National de la Recherche Scientifique; FranciaFil: Del Bel, Elaine. Universidade de Sao Paulo; BrasilFil: Papy García, Dulce. Université Paris Est Créteil; FranciaFil: Chehin, Rosana Nieves. Universidad Nacional de Tucuman. Instituto de Investigaciones En Medicina Molecular y Celular Aplicada del Bicentenario. - Gobierno de la Provincia de Tucuman. Ministerio de Salud. Sistema Provincial de Salud. Instituto de Investigaciones En Medicina Molecular y Celular Aplicada del Bicentenario. - Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet Noa Sur. Instituto de Investigaciones En Medicina Molecular y Celular Aplicada del Bicentenario.; ArgentinaFil: Michel, Patrick P.. Sorbonne University; Francia. Centre National de la Recherche Scientifique; FranciaFil: Raisman Vozari, Rita. Sorbonne University; Francia. Centre National de la Recherche Scientifique; Franci