On the Quantum Chromodynamics of a Massive Vector Field in the Adjoint Representation

In this paper, we explore the possibility of constructing the quantum chromodynamics of a massive color-octet vector field without introducing higher structures like extended gauge symmetries, extra dimensions or scalar fields. We show that gauge invariance is not enough to constraint the couplings. Nevertheless the requirement of unitarity fixes the values of the coupling constants, which otherwise would be arbitrary. Additionally, it opens a new discrete symmetry which makes the coloron stable and avoid its resonant production at a collider. On the other hand, a judicious definition of the gauge fixing terms modifies the propagator of the massive field making it well-behaved in the ultra-violet limit. The relation between our model and the more general approach based on extended gauge symmetries is also discussed.Comment: Subsection 2.1 rewritten in order to make it more pedagogical. This version match the text accepted in IJMP

Meeting new readers in the transition to digital newspapers: lessons from the entertainment industry

In this work, carried out at the University of California Los Angeles (UCLA) Center for Management of Enterprise Media, Entertainment,and Sports (Memes), we suggest that there is hope and reason for media companies to expect a recovery from the current crisis. As journalists and researchers in communication, we are concerned about newspapers’ sustainability, and we refuse to consider a future scenario without the press. According to this objective we focus on the entertainment industry with the goal of learning from it how to survive and even grow despite freely available content on the Web. We consider the unstoppable growth in users and revenue experienced by Netflix, Amazon and iTunes, and pull from it lessons learned that might help newspapers to navigate the digital landscape. Our hypothesis is that digital newspapers can find new readers in the segment of digital consumers who already “pay” for digital content including streaming movies and television shows. Sales, subscriptions, and online rentals experienced significant growth in 2013, bringing them closer to the sales figures of hardware such as DVDs and blu-ray discs. And, although piracy is an issue in the entertainment industry, there remains room for revenue growth

Razón autónoma y modelos matemáticos de la acción

El supuesto de la autonomía de la razón obliga a recurrir a la Matemática para explicar su hipotética practicidad. Esto plantea problemas nada sencillos de resolver. Se revisa brevemente el reciente enfoque de la racionalidad limitada, sus potencialidades y debilidades. Se cuestiona la posibilidad misma de una teoría pura de la acción

El mercado entre la sociabilidad y el conflicto

Different opinions are expounded about the relation between market and political community. This relation is two-sided. On the one hand, it is collaborative; on the other, it is conflictive. Attempts to harmonize the individual interests mechanically have failed both theoretically and in practice

Don y desarrollo, bases de la economía.

El autor presenta algunas reflexiones y conclusiones que se pueden extraerde la lectura de Caritas in veritate, desde la perspectiva de la filosofía de la economía. En un primer momento se subraya, a la luz de la encíclica, la importancia de considerar el hombre como un don en sí mismo. A partir de ahí, se explica la concepción adecuada del desarrollo, también desde la óptica del don. Desde esas coordenadas, la teoría económica es interpelada para introducir la lógica del don y del amor en la comprensión de la acción económica, huyendo así del peligro de una racionalidad mutilada. En particular se sugiere la conexión entre don y contrato para hacer posible el auténtico desarrollo. Documentos del Instituto de Antropología y Ética, número 1

Evaluation of nutritional value of the artichoke (Cynara scolymus) in the laying quails production

P?ginas 15-21En el presente estudio se evalu? el valor nutricional de la alcachofa (Cynara scolymus) suministrada a codornices de postura (Coturnix jap?nica). Se determin? sus efectos en par?metros productivos, costos de alimentaci?n, niveles de colesterol y triglic?ridos sangu?neos, pH fecal, microbiolog?a del tracto intestinal, heces, histolog?a del intestino delgado y alometr?a de ?rganos digestivos. Se emplearon 90 codornices de postura divididas en 5 tratamientos, 3 r?plicas y 6 aves en cada una, alimentadas por diez semanas. Los tratamientos 1, 2, 3, 4 y 5 conten?an alcachofa en 0%, 1%, 2%, 3% y 4% en la dieta, respectivamente. Los resultados de las variables productivas no mostraron diferencias significativas (p<0.05), al igual que el pH fecal, colesterol sangu?neo, ancho de vellosidades intestinales y peso de los ?rganos digestivos. A pesar de ello los mejores resultados se encontraron en los animales alimentados con alcachofa. En el peso del huevo (10.07g vs. 10.63g), niveles de triglic?ridos sangu?neos (837 mg/dl vs. 379.3 mg/dl), longitud de vellosidades (242.13 ?m vs. 382.8 ?m) y profundidad de las criptas (51.9 ?m vs. 71.5 ?m) se encontraron diferencias significativas (p<0.05). No se aisl? Salmonella en ninguno de los tratamientos y un conteo menor de coliformes fecales se observ? en los tratamientos con alcachofa. Se determin? que el tratamiento cinco fue el de menor costo de producci?n parcial. Se concluye que la inclusi?n de alcachofa en la alimentaci?n de codornices de postura mejora los resultados productivos y las funciones fisiol?gicas intestinales de los animales.ABSTRACT. Nutritional value of the artichoke (Cynara scolymus) in the production of laying quails was evaluated, determining its effects in the productive parameters, nourishment costs, levels of cholesterol and triglycerides in the blood, fecal pH, microbiology of the intestinal tract and faeces, histology of the small intestine and allometry of digestive organs. 90 laying quails were used, which were divided into 5 treatments, 3 replicas and 6 birds in each one, they were fed for ten weeks. Treatments 1, 2, 3, 4 and 5 contained artichoke in 0%, 1%, 2%, 3% and 4% of inclusion in the diet, respectively. Neither the results of the productive variables, nor the fecal pH, cholesterol in the blood, width of intestinal down and weight of digestive organs showed significant differences (p<0.05). However the best results were in the animals fed with artichoke. In the weight of the egg (10.07 g vs. 10.63 g), levels of triglycerides in the blood (837 mg/dl vs. 379.3 mg/dl), length of down (242, 13 ?m vs. 382.8 ?m) and depth of crypts (51,9 ?m vs. 71.5 ?m) significant differences were found (p<0.05). Salmonella was not isolated in any of the treatments and a smaller count of fecal coliforms was determined in the treatments with artichoke. Treatment 5 had the lowest cost in partial production. In sum, the inclusion of artichoke in the feeding of laying quails improves both the productive results and the intestinal physiological functions of animals

From plasmodesma geometry to effective symplasmic permeability through biophysical modelling

Regulation of molecular transport via intercellular channels called plasmodesmata (PDs) is important for both coordinating developmental and environmental responses among neighbouring cells, and isolating (groups of) cells to execute distinct programs. Cell-to-cell mobility of fluorescent molecules and PD dimensions (measured from electron micrographs) are both used as methods to predict PD transport capacity (i.e., effective symplasmic permeability), but often yield very different values. Here, we build a theoretical bridge between both experimental approaches by calculating the effective symplasmic permeability from a geometrical description of individual PDs and considering the flow towards them. We find that a dilated central region has the strongest impact in thick cell walls and that clustering of PDs into pit fields strongly reduces predicted permeabilities. Moreover, our open source multi-level model allows to predict PD dimensions matching measured permeabilities and add a functional interpretation to structural differences observed between PDs in different cell walls

La ética y el derecho en la producción y el consumo del entretenimiento

Contiene las ponencias y comunicaciones del congreso