Financial Liberalization and Emerging Stock Market Volatility

In this paper we test whether volatility in six emerging markets has changed significantly over the period 1976:01-2002:03. This period corresponds to the years of more profound development of both the financial and the productive sides in emerging countries. We use alternative methodologies of of endogenous breakpoints detection that estimate the dates at which the behavior of the sotck market volatility changed. The analysis suggests that volatility has behaved in a di¤erent manner over the periodemerging markets, volatility, multiple structural breaks

Analysis of the Level of Immersion of 360º Video Features Produced by Spanish Media

This paper offers the results of a content analysis on the level of immersion in 360º video features produced by Spanish media. Unlike other conventional ways of storytelling, this new modality provides the viewer with a sensation of being really immerse in a reality that is only being represented, which favors a deeper and more meaningful understanding of it. Our study is divided in three sections. Firstly, we develop a brief theoretical framework that includes the definition and foundations on which immersive feature is based. From this theoretical foundation, we draw a scale to measure the immersion level of these pieces and we confront our proposal to the qualified assessment of 10 experts. Finally we apply this scale on a sample of 148 360º video features produced by Spanish media between January 2015 and December 2017. The aim is to analyze its use and also to infer some good practices that can be useful not only for scholars researching on this new format but also for practitioners producing it.El presente trabajo ofrece los resultados de un análisis de contenido sobre el nivel de inmersión en los vídeos en 360º producidos por medios periodísticos españoles. A diferencia de otras maneras convencionales de contar, esta nueva modalidad genera en el espectador la sensación de encontrarse realmente presente en una realidad que está siendo solo representada. Esto favorece una comprensión más profunda y significativa de ella. Nuestro estudio está dividido en tres secciones. En primer lugar, desarrollamos un breve marco teórico en el que recogemos la definición y fundamentos sobre los que se sostiene el periodismo inmersivo en general y el reportaje en vídeo en 360º en particular. A partir de esta fundamentación, proponemos una escala para medir el nivel de inmersión que hace posible este tipo de piezas y la validamos mediante la evaluación cualificada de un grupo de 10 expertos. Finalmente, aplicamos esta escala sobre una muestra de 148 reportajes en vídeo en 360º publicados por medios periodísticos españoles durante el período comprendido entre enero de 2015 y diciembre de 2017. El objetivo es analizar su uso e inferir una serie de buenas prácticas que puedan resultar de utilidad tanto a académicos que investigan este nuevo formato como a los profesionales que lo producen

The effect of a stellar magnetic variation on the jet velocity

Stellar jets are normally constituted by chains of knots with some periodicity in their spatial distribution, corresponding to a variability of order of several years in the ejection from the protostar/disk system. A widely accepted theory for the presence of knots is related to the generation of internal working surfaces due to variations in the jet ejection velocity. In this paper we study the effect of variations in the inner disk-wind radius on the jet ejection velocity. We show that a small variation in the inner disk-wind radius produce a variation in the jet velocity large enough to generate the observed knots. We also show that the variation in the inner radius may be related to a variation of the stellar magnetic field.Comment: 5 pages, 3 figures, accepted for publication in Ap

Effect of progressive inoculation of fauna-free sheep with holotrich protozoa and total-fauna on rumen fermentation, microbial diversity and methane emissions

Rumen methanogenesis represents an energy waste for the ruminant and an important source of greenhouse gas; thus, integrated studies are needed to fully understand this process. Eight fauna-free sheep were used to investigate the effect of successive inoculation with holotrich protozoa then with total fauna on rumen methanogenesis. Holotrichs inoculation neither altered rumen fermentation rate nor diet digestibility, but increased concentrations of acetate (+15%), butyrate (+57%), anaerobic fungi (+0.82 log), methanogens (+0.41 log) and methanogenesis (+54%). Further inoculation with total fauna increased rumen concentrations of protozoa (+1.0 log), bacteria (+0.29 log), anaerobic fungi (+0.78 log), VFA (+8%), ammonia and fibre digestibility (+17%) without affecting levels of methanogens or methanogenesis. Rumen methanogens population was fairly stable in terms of structure and diversity, while the bacterial community was highly affected by the treatments. Inoculation with holotrich protozoa increased bacterial diversity. Further inoculation with total fauna lowered bacterial diversity but increased concentrations of certain propionate and lactate-producing bacteria, suggesting that alternative H(2) sinks could be relevant. This experiment suggests that holotrich protozoa have a greater impact on rumen methanogenesis than entodiniomorphids. Thus, further research is warranted to understand the effect of holotrich protozoa on methane formation and evaluate their elimination from the rumen as a potential methane mitigation strategy

Study of methanogen communities associated with different rumen protozoal populations

Protozoa-associated methanogens (PAM) are considered one of the most active communities in the rumen methanogenesis. This experiment investigated whether methanogens are sequestrated within rumen protozoa, and structural differences between rumen free-living methanogens and PAM. Rumen protozoa were harvested from totally faunated sheep, and six protozoal fractions (plus free-living microorganisms) were generated by sequential filtration. Holotrich-monofaunated sheep were also used to investigate the holotrich-associated methanogens. Protozoal size determined the number of PAM as big protozoa had 1.7–3.3 times more methanogen DNA than smaller protozoa, but also more endosymbiotic bacteria (2.2- to 3.5-fold times). Thus, similar abundance of methanogens with respect to total bacteria were observed across all protozoal fractions and free-living microorganisms, suggesting that methanogens are not accumulated within rumen protozoa in a greater proportion to that observed in the rumen as a whole. All rumen methanogen communities had similar diversity (22.2 ± 3.4 TRFs). Free-living methanogens composed a conserved community (67% similarity within treatment) in the rumen with similar diversity but different structures than PAM (P < 0.05). On the contrary, PAM constituted a more variable community (48% similarity), which differed between holotrich and total protozoa (P < 0.001). Thus, PAM constitutes a community, which requires further investigation as part of methane mitigation strategies

Bacterial protein degradation by different rumen protozoal groups

Bacterial predation by protozoa has the most deleterious effect on the efficiency of N use within the rumen, but differences in activity among protozoal groups are not completely understood. Two in vitro experiments were conducted to identify the protozoal groups more closely related with rumen N metabolism. Rumen protozoa were harvested from cattle and 7 protozoal fractions were generated immediately after sampling by filtration through different nylon meshes at 39°C, under a CO2 atmosphere to maintain their activity. Protozoa were incubated with 14C-labeled bacteria to determine their bacterial breakdown capacity, according to the amount of acid-soluble radioactivity released. Epidinium tended to codistribute with Isotricha and Entodinium with Dasytricha; therefore, their activity was calculated together. This study demonstrated that big Diplodiniinae had the greatest activity per cell (100 ng bacterial CP per protozoa and hour), followed by Epidinium plus Isotricha (36.4), small Diplodiniinae (34.2), and Entodinium plus Dasytricha (14.8), respectively. However, the activity per unit of protozoal volume seemed to vary, depending on the protozoal taxonomy. Small Diplodiniinae had the greatest activity per volume (325 ng bacterial CP per protozoal mm3 and hour), followed by big Diplodiniinae (154), Entodinium plus Dasytricha (104), and Entodinium plus Dasytricha (25.6). A second experiment was conducted using rumen fluid from holotrich-monofaunated sheep. This showed that holotrich protozoa had a limited bacterial breakdown capacity per cell (Isotricha 9.44 and Dasytricha 5.81 ng bacterial CP per protozoa and hour) and per protozoal volume (5.97 and 76.9 ng bacterial CP per protozoal mm3 and hour, respectively). Therefore, our findings indicated that a typical protozoal population (106 total protozoa/mL composed by Entodinium sp. 88%, Epidinium sp. 7%, and other species 4%) is able to break down ∼17% of available rumen bacteria every hour. Entodinium sp. is responsible for most of this bacterial breakdown (70 to 75%), followed by Epidinium sp. (16 to 24%), big Diplodiniinae (4 to 6%), and small Diplodiniinae (2 to 6%), whereas holotrich protozoa have a negligible activity (Dasytricha sp. 0.6 to 1.2% and Isotricha sp. 0.2 to 0.5%). This in vitro information must be carefully interpreted, but it can be used to indicate which protozoal groups should be suppressed to improve microbial protein synthesis in vivo.This study was supported by the Framework 7 program from the EU “Innovative and practical management approaches to reduce nitrogen excretion by ruminants (Rednex)” and the Welsh government. We thank the Institute of Biological, Environmental and Rural Sciences staff for their assistance and collaboration

Nuevo método experimental para la determinación de condiciones de ignición

Tesis-Universidad Complutense de Madrid, 1.970.Fac. de Ciencias QuímicasTRUEProQuestpu

Nuevo método experimental para la determinación de condiciones de ignición

Tesis-Universidad Complutense de Madrid, 1.970.Fac. de Ciencias QuímicasTRUEProQuestpu

Geometrical origin of the *-product in the Fedosov formalism

The construction of the *-product proposed by Fedosov is implemented in terms of the theory of fibre bundles. The geometrical origin of the Weyl algebra and the Weyl bundle is shown. Several properties of the product in the Weyl algebra are proved. Symplectic and abelian connections in the Weyl algebra bundle are introduced. Relations between them and the symplectic connection on a phase space M are established. Elements of differential symplectic geometry are included. Examples of the Fedosov formalism in quantum mechanics are given.Comment: LaTeX, 39 page