Scalar-Vector Bootstrap

We work out all of the details required for implementation of the conformal bootstrap program applied to the four-point function of two scalars and two vectors in an abstract conformal field theory in arbitrary dimension. This includes a review of which tensor structures make appearances, a construction of the projectors onto the required mixed symmetry representations, and a computation of the conformal blocks for all possible operators which can be exchanged. These blocks are presented as differential operators acting upon the previously known scalar conformal blocks. Finally, we set up the bootstrap equations which implement crossing symmetry. Special attention is given to the case of conserved vectors, where several simplifications occur.Comment: 76 pages, v3 moved several details into appendices, expanded discussion of mixed symmetry projecto

Geodesic Diagrams, Gravitational Interactions & OPE Structures

We give a systematic procedure to evaluate conformal partial waves involving symmetric tensors for an arbitrary CFT$_d$ using geodesic Witten diagrams in AdS$_{d+1}$. Using this procedure we discuss how to draw a line between the tensor structures in the CFT and cubic interactions in AdS. We contrast this map to known results using three-point Witten diagrams: the maps obtained via volume versus geodesic integrals differ. Despite these differences, we show how to decompose four-point exchange Witten diagrams in terms of geodesic diagrams, and we discuss the product expansion of local bulk fields in AdS.Comment: typos corrected, references adde

Los retos de la sustentabilidad urbana en México. Reflexiones sobre su evaluación a través de la Metodología ICES del BID

En 2000, la Organización de Naciones Unidas mencionó que, en el siglo XX, México, como muchos países latinoamericanos, sufrió un proceso de urbanización muy acelerado que provocó graves problemas de bienestar,seguridad y convivencia familiar y social (ONU, 2000).El crecimiento urbano acelerado y la falta de planeación en el territorio han generado diversos problemas socio espaciales, económicos y ambientales. Además, se ha generado el crecimiento exponencial de las ciudades medias de la región. En 2014, el 54% de la población mundial vivía en ciudades y la ONU estima que para el 2050 la cifra llegará al 66% (ONU-Hábitat, 2016). La región de América Latina y el Caribe (ALyC) es la segunda más urbanizada del mundo; en 1950, la tasa de urbanización era de 4%; en 2010 de 79%; entre 1950 y 2014 su población urbana aumentó del 50% al 80%, y se espera que alcance el 86% en 2050 (BID, 2017). En este sentido, el estudio y análisis del desarrollo urbano en las ciudades medias, permite identificar el problema, y priorizar los retos, a fin de poder evitar que estos impactos se conviertan en grandes conflictos para las ciudades. Este artículo es producto de una investigación sobre la sustentabilidad integral en las zonas metropolitanas de Tampico y Toluca; y tiene como propósito reflexionar sobre la sustentabilidad urbana en México así como de los retos actuales. Se inicia a partir del crecimiento urbano en México, y presenta una revisión de los antecedentes hasta abordar el tema de la sustentabilidad del desarrollo. Finalmente, se analizan los problemas implicados en la sustentabilidad de las ciudades, particularizando en las zonas metropolitanas de estudio.Universidad Autónoma del Estado de México - CONACY

Topological lattice actions for the 2d XY model

We consider the 2d XY Model with topological lattice actions, which are invariant against small deformations of the field configuration. These actions constrain the angle between neighbouring spins by an upper bound, or they explicitly suppress vortices (and anti-vortices). Although topological actions do not have a classical limit, they still lead to the universal behaviour of the Berezinskii-Kosterlitz-Thouless (BKT) phase transition - at least up to moderate vortex suppression. In the massive phase, the analytically known Step Scaling Function (SSF) is reproduced in numerical simulations. However, deviations from the expected universal behaviour of the lattice artifacts are observed. In the massless phase, the BKT value of the critical exponent eta(c) is confirmed. Hence, even though for some topological actions vortices cost zero energy, they still drive the standard BKT transition. In addition we identify a vortex-free transition point, which deviates from the BKT behaviour

ANÃLISIS DE RENTABILIDAD DE LA PRODUCCIÓN Y VENTA DE POLLO EN CANAL EN EL MUNICIPIO DE ACANCEH, YUCATÃN, MÉXICO

We evaluated the profitability of the project from a broiler production unit for marketing in channel two outlets, through the economic assessment indicators: Net Present Value and Internal Rate of Return. Based on the results obtained we conclude that the project was profitable.Broiler chicken production, chicken carcass, profitability, economic indicators., Agribusiness,

CARACTERIZACIÓN DE LOS AGENTES COMERCIALES: SUPERMERCADOS Y RESTAURANTES, EN LA DINÃMICA DEL MERCADO DE LAS SETAS PLEUROTUS OSTREATUS EN MÉRIDA, YUCATÃN, MÉXICO

Mushrooms are one of the organisms the nature that have a great capacity to adapt and develop in different weather conditions and in different agricultural environments. Mushrooms also make an important contribution to the satisfaction of some human necessities by the input of nutritional and medicinal products due to a wide diversity of properties that they posses. In addition, its production generates incomes and employment, for these reasons, the farming of mushrooms is a very important activity socially, economical and ecologically. In Yucatán, the farming of the mushroom “Pleurotus ostreatus “represents an option for the sustainable development of poor rural communities. Based on the previous assumptions, the objective of the present work was to describe the consumption of mushrooms in the city of Mérida, Yucatán, México, through the perspective of two types of retailers: supermarkets and restaurants. The information could be used to facilitate successful access to the market for the mushroom producers. A cross-sectional descriptive study with a quantitative approach was done, in which the sample was formed by 15 supermarkets and 28 restaurants. The techniques of direct observation and interview were used. Based on the obtained result, which concludes that the acceptance of the mushroom “pleurotus ostreatus†is growing among the yucatecan population and represents a good option for the sustainable development of the small producers.Mushrooms, market, retailers, demand., Agribusiness,

Cl diffusion in CdTe solar cells activated by gaseous CHClF2 atmosphere

The activation treatment is consider of dramatic importance for CdTe solar cells. The most effective activation processes are based on chlorine compounds. However it is still not clear how Cl diffusion depends on the chlorination method. In this paper we activated CdTe solar cells by gaseous CHClF2 and investigated the Cl presence by TEM and XPS. Preliminary results show clear presence of Cl trapped at the CdS/CdTe interface. Thanks to the flexibility of the gaseous activation treatment, further samples will be prepared in order to force larger quantity of Cl into the absorber and they will be similarly analyzed. TEM will be used to investigate Cl presence at grain boundaries and XPS to determine the compounds formed by Cl

ANÃLISIS DE RENTABILIDAD DE DOS ALTERNATIVAS DE ALIMENTACIÓN NO CONVENCIONALES EN LA PRODUCCIÓN DE CONEJOS EN EL MUNICIPIO DE TIXPEHUAL, YUCATÃN, MÉXICO

Profitability of a rabbit's production unit was evaluated through the analysis of two nonconventional food alternatives (mixing tulip forage, ramon forage and balanced food) compared with the conventional food (balanced food). For analyse the profitability, economic assessment indicators were used: the Net Present Value and the Internal Rate of Return. Based in the obtained results, this study concludes that the more profitable alternative was the ramon forage and balanced food.Rabbit production, profitability, economic indicators., Agribusiness,

Visual attention to alcohol labels:An exploratory eye-tracking experiment

Current alcohol labelling goes unnoticed by consumers. In addition, EU legislation does not obligate the alcohol industry to include any health warning labels on alcohol packagings. This study aims to explore how the size and design of alcohol by volume (ABV) labels, along with the alcohol strength presented on these labels, influence visual attention toward them. We also examine how label size and alcohol strength influence visual attention toward a health warning label on alcoholic beverages. Using an experimental human laboratory design, we tracked the eye-movements of 64 participants while they viewed beers with different ABV (0.4%, 4.6% vs. 15%). We measured the number of fixations toward ABV labelling which varied in size and design (text-only vs. traffic light). A health warning label was also included on the beers for half of the participants and size was manipulated as a between-subject factor. Results showed strong evidence that the number of fixations was higher when the ABV labels were larger and used a traffic light system. Likewise, we found a higher number of fixations toward larger health warning labels and differences in visual attention depending on the ABV content presented. In conclusion, this study indicates that current alcohol labelling is insufficient to draw the attention of consumers and suggests that future alcohol labelling must be larger and with a graphic design to attract attention.</p