Three-dimensional fractional-spin gravity

Using Wigner-deformed Heisenberg oscillators, we construct 3D Chern--Simons models consisting of fractional-spin fields coupled to higher-spin gravity and internal non-abelian gauge fields. The gauge algebras consist of Lorentz-tensorial Blencowe-Vasiliev higher-spin algebras and compact internal algebras intertwined by infinite-dimensional generators in lowest-weight representations of the Lorentz algebra with fractional spin. In integer or half-integer non-unitary cases, there exist truncations to gl(N,N +/- 1) or gl(N|N +/- 1) models. In all non-unitary cases, the internal gauge fields can be set to zero. At the semi-classical level, the fractional-spin fields are either Grassmann even or odd. The action requires the enveloping-algebra representation of the deformed oscillators, while their Fock-space representation suffices on-shell.Comment: 38 pages, 2 tables. References [7,13,61] added with comments in the second version. To appear in JHE

Gravitational and gauge couplings in Chern-Simons fractional spin gravity

We provide a necessary and sufficient condition for the consistency of the supertrace, through the existence of a certain ground state projector. We build this projector and check its properties to the first two orders in the number operator and to all orders in the deformation parameter. We then find the relation between the gravitational and internal gauge couplings in the resulting unified three-dimensional Chern--Simons theory for Blencowe--Vasiliev higher spin gravity coupled to fractional spin fields and internal gauge potentials. We also examine the model for integer or half-integer fractional spins, where infinite dimensional ideals arise and decouple, leaving finite dimensional gauge algebras $gl(2l+1)$ or $gl(l|l+1)$ and various real forms thereof.Comment: Published in JHEP. 32 pages, 3 figure

‘Money and (dis)connection’: Income inequality and network disadvantage as barriers to sustainable technology adoption

Scholars have highlighted the role of income distribution as a fundamental factor to understand consumption, health, adoption of technologies, social cohesion, democratic stability, and long term economic performance, among other phenomena. Moreover, reducing income inequality was included in the United Nations’ Sustainable Development Goals. However, less attention has been put on the link between differences in household incomes and other pressing sustainability challenges, such as those that depend on massive adoption of new technologies within network industry sectors: telecommunications, waste management, transport, energy and water. Does existent income inequality translate into adoption gaps within these sectors? Is inequality an obstacle for advancing the vision of an inter-connected and more sustainable world? This research explores these questions through seven stand-alone papers, which focus on adoption of broadband internet, municipal recycling and railway passenger transport. Part I of the thesis includes four papers based on publicly available data from traditional mainstream sources. Chapter 1 provides a systematic map of the peer-reviewed literature on the link between income inequality and adoption of the three selected network technologies. Chapter 2 looks at country-level panel data from OECD countries. Chapter 3 analyses cross-sectional data in a broader world-wide sample. Chapter 4 compares borough-level recycling and income distribution in two European cities: London (United Kingdom) and Barcelona (Spain). Part II provides an in-depth analysis of two South American metropolitan areas: Santiago (Chile) and Medellín (Colombia). This part includes three papers (chapters 5, 6 and 7), each one focusing on a specific sector, that employ mixed-methods based on fieldwork conducted in both cities. The main contributions of the thesis are new evidence on the negative effect of income inequality on network technology adoption, and a discussion of the role of formal and informal institutions in this relationship.CONICYT PFCHA/DOCTORADO BECAS CHILE/2016 ‐ 7217012

Action principles for higher and fractional spin gravities

We review various off-shell formulations for interacting higher-spin systems in dimensions 3 and 4. Associated with higher-spin systems in spacetime dimension 4 is a Chern-Simons action for a superconnection taking its values in a direct product of an infinite-dimensional algebra of oscillators and a Frobenius algebra. A crucial ingredient of the model is that it elevates the rigid closed and central two-form of Vasiliev's theory to a dynamical 2-form and doubles the higher-spin algebra, thereby considerably reducing the number of possible higher spin invariants and giving a nonzero effective functional on-shell. The two action principles we give for higher-spin systems in 3D are based on Chern-Simons and BF models. In the first case, the theory we give unifies higher-spin gauge fields with fractional-spin fields and an internal sector. In particular, Newton's constant is related to the coupling constant of the internal sector. In the second case, the BF action we review gives the fully nonlinear Prokushkin-Vasiliev, bosonic equations for matter-coupled higher spins in 3D. We present the truncation to a single, real matter field relevant in the Gaberdiel-Gopakumar holographic duality. The link between the various actions we present is the fact that they all borrow ingredients from Topological Field Theory. It has bee conjectured that there is an underlying and unifying 2-dimensional first-quantised description of the previous higher-spin models in 3D and 4D, in the form of a Cattaneo-Felder-like topological action containing fermionic fields.Comment: 41+1 pages. References added and reorganized, corrected typos, last paragraph of section 2 re-written. Contribution to the proceedings of the International Workshop on Higher Spin Gauge Theories (4-6 November 2015, Singapore

The most influential countries in market orientation: A bibliometric analysis between 1990 and 2016

© The Author(s) 2018. The purpose of this article is to analyze the most productive and influential countries engaging in market orientation (MO) research between 1990 and 2016. This article shows the general trajectories of these countries, the relationships among them, and their research in the area of MO by analyzing results on citations and publications. The article uses applied bibliometric techniques on available information found in the Web of Science. The results show that the 10 leading countries produce more than 70% of total publications, where the United States leads in all indicators, followed by the United Kingdom and China. Furthermore, although there has been a steady increase in overall number of publications, this trend is not shared evenly among different nations

Localizing Protein in 3D Neural Stem Cell Culture: a Hybrid Visualization Methodology

The importance of 3-dimensional (3D) topography in influencing neural stem and progenitor cell (NPC) phenotype is widely acknowledged yet challenging to study. When dissociated from embryonic or post-natal brain, single NPCs will proliferate in suspension to form neurospheres. Daughter cells within these cultures spontaneously adopt distinct developmental lineages (neurons, oligodendrocytes, and astrocytes) over the course of expansion despite being exposed to the same extracellular milieu. This progression recapitulates many of the stages observed over the course of neurogenesis and gliogenesis in post-natal brain and is often used to study basic NPC biology within a controlled environment. Assessing the full impact of 3D topography and cellular positioning within these cultures on NPC fate is, however, difficult. To localize target proteins and identify NPC lineages by immunocytochemistry, free-floating neurospheres must be plated on a substrate or serially sectioned. This processing is required to ensure equivalent cell permeabilization and antibody access throughout the sphere. As a result, 2D epifluorescent images of cryosections or confocal reconstructions of 3D Z-stacks can only provide spatial information about cell position within discrete physical or digital 3D slices and do not visualize cellular position in the intact sphere. Here, to reiterate the topography of the neurosphere culture and permit spatial analysis of protein expression throughout the entire culture, we present a protocol for isolation, expansion, and serial sectioning of post-natal hippocampal neurospheres suitable for epifluorescent or confocal immunodetection of target proteins. Connexin29 (Cx29) is analyzed as an example. Next, using a hybrid of graphic editing and 3D modelling softwares rigorously applied to maintain biological detail, we describe how to re-assemble the 3D structural positioning of these images and digitally map labelled cells within the complete neurosphere. This methodology enables visualization and analysis of the cellular position of target proteins and cells throughout the entire 3D culture topography and will facilitate a more detailed analysis of the spatial relationships between cells over the course of neurogenesis and gliogenesis in vitro

Localizing Protein in 3D Neural Stem Cell Culture: a Hybrid Visualization Methodology

The importance of 3-dimensional (3D) topography in influencing neural stem and progenitor cell (NPC) phenotype is widely acknowledged yet challenging to study. When dissociated from embryonic or post-natal brain, single NPCs will proliferate in suspension to form neurospheres. Daughter cells within these cultures spontaneously adopt distinct developmental lineages (neurons, oligodendrocytes, and astrocytes) over the course of expansion despite being exposed to the same extracellular milieu. This progression recapitulates many of the stages observed over the course of neurogenesis and gliogenesis in post-natal brain and is often used to study basic NPC biology within a controlled environment. Assessing the full impact of 3D topography and cellular positioning within these cultures on NPC fate is, however, difficult. To localize target proteins and identify NPC lineages by immunocytochemistry, free-floating neurospheres must be plated on a substrate or serially sectioned. This processing is required to ensure equivalent cell permeabilization and antibody access throughout the sphere. As a result, 2D epifluorescent images of cryosections or confocal reconstructions of 3D Z-stacks can only provide spatial information about cell position within discrete physical or digital 3D slices and do not visualize cellular position in the intact sphere. Here, to reiterate the topography of the neurosphere culture and permit spatial analysis of protein expression throughout the entire culture, we present a protocol for isolation, expansion, and serial sectioning of post-natal hippocampal neurospheres suitable for epifluorescent or confocal immunodetection of target proteins. Connexin29 (Cx29) is analyzed as an example. Next, using a hybrid of graphic editing and 3D modelling softwares rigorously applied to maintain biological detail, we describe how to re-assemble the 3D structural positioning of these images and digitally map labelled cells within the complete neurosphere. This methodology enables visualization and analysis of the cellular position of target proteins and cells throughout the entire 3D culture topography and will facilitate a more detailed analysis of the spatial relationships between cells over the course of neurogenesis and gliogenesis in vitro

Uso de las TIC y desarrollo profesional docente de la unidad educativa “Carlos Alberto Aguirre Avilés” de Ecuador, 2019

La tesis denominada Uso de las TIC y desarrollo profesional docente de la Unidad Educativa “Carlos Alberto Aguirre Avilés” de Ecuador, 2019, elaborada con la finalidad de obtener el grado académico de Maestro en Administración de la Educación, tuvo como objetivo el determinar la relación entre el uso de las TIC y el desarrollo profesional docente de la Unidad Educativa, el estudio, asumió el enfoque cuantitativo, tipo no experimental, y diseño correlacional, la población, estuvo conformado por 47 docentes y la muestra de tipo censal, en cuanto a la técnica utilizada, fue la encuesta, y los instrumentos, fueron dos cuestionarios, finalmente se llegó a las conclusiones que, el uso de las TIC y el desarrollo profesional docente cuentan con una correlacionan positiva considerable según el coeficiente de correlación Rho de Spearman de 0,716, siendo 37 docentes que representan el 78,7% que cuentan con un nivel regular para ambas variables, la gestión de la información del entorno virtual y el desarrollo profesional docente, cuenta con una correlación positiva media, conforme el Coeficiente de correlación. Rho de Spearman de 0,375 y de la misma manera, son 28 docentes, el 59,6%, los que cuentan con un nivel regular coincidente, el interactuar en entornos virtuales y el desarrollo profesional docente, tienen una correlación positiva considerable, conforme el Coeficiente de correlación. Rho de Spearman, cuyo valor encontrado fue de 0,575, así también es el 70,2%, de los docentes que tienen una interacción buena y la creación de los objetos virtuales en diversos formatos y el desarrollo profesional docente, tienen una correlación positiva considerable, conforme al valor de 0,650, de Coeficiente de correlación de Rho de Spearman, siendo 33 docentes, que representan el 70,2%, los que cuentan con un nivel regular en ambos aspectos

Asociación entre síndrome de ovario poliquístico y dislipidemias en mujeres de edad reproductiva fértil

La investigación tiene como objetivo determinar la asociación entre síndrome de ovario poliquístico y dislipidemia en mujeres de edad reproductiva fértil en el Hospital Albrecht. La metodología que se siguió fue de tipo básica, con diseño no experimental, de corte transversal y analítica. Se tuvo una muestra de 300 mujeres atendidas en el servicio de ginecología, para ello se usaron las historias clínicas para la recopilación de la información. La frecuencia de síndrome de ovario poliquístico fue de 148(49%) y la de dislipidemia fue de 143(48%). La frecuencia dedislipidemia en pacientes con SOP fue de 109(76.2%), la mayoría con niveles de triglicéridos elevados y niveles bajos de HDL. Se concluyó que el tener SOP incrementó la probabilidad de tener dislipidemia, después de ajustar por confusores (RPa: 2.95; IC 95%: 2.20 - 3.95; p=0.001