A tale of tails through generalized unitarity

We introduce a novel framework to study high-order gravitational effects on a binary from the scattering of its emitted gravitational radiation. Here we focus on the radiation-reaction due to the background of the binary's gravitational potential, namely on the so-called tail effects. We start from the effective field theory of a binary composite-particle, and through multi-loop, and generalized-unitarity methods, we derive the causal effective actions of the dynamical multipoles, the energy spectra, and the observable flux due to these effects. We proceed through the third subleading such radiation-reaction effect, at the four-loop level and seventh order in post-Newtonian gravity, shedding new light on the higher-order effects, and completing the state of the art.Comment: 7 pp, 3 figure

An SU(5)⊗\otimesZ_{13} Grand Unification Model

We propose an SU(5) grand unified model with an invisible axion and the unification of the three coupling constants which is in agreement with the values, at $M_Z$, of $\alpha$, $\alpha_s$, and $\sin^2\theta_W$. A discrete, anomalous, $Z_{13}$ symmetry implies that the Peccei-Quinn symmetry is an automatic symmetry of the classical Lagrangian protecting, at the same time, the invisible axion against possible semi-classical gravity effects. Although the unification scale is of the order of the Peccei-Quinn scale the proton is stabilized by the fact that in this model the standard model fields form the SU(5) multiplets completed by new exotic fields and, also, because it is protected by the $Z_{13}$ symmetry.Comment: 14 pages, more typos correcte

Qualitative Assessment of User Acceptance within Action Design Research and Action Research: Two Case Studies

Nowadays, there are several models to evaluate technological acceptance of software developed through Action Design Research and Action Research. These models rely on quantitative techniques to study user behavioural intentions and thus predict the use of a technology. This paper presents our experiences in using qualitative methods to assess such acceptance in the development of specialized tools for Strategic Scanning. Our study suggests that qualitative methods can be an alternative to evaluate technology acceptance in situations where the number of users is small or where there are requirements for continuous improvement

Revealing the Landscape of Globally Color-Dual Multi-loop Integrands

We report on progress in understanding how to construct color-dual multi-loop amplitudes. First we identify a cubic theory, semi-abelian Yang-Mills, that unifies many of the color-dual theories studied in the literature, and provides a prescriptive approach for constructing $D$-dimensional color-dual numerators through one-loop directly from Feynman rules. By a simple weight counting argument, this approach does not further generalize to two-loops. As a first step in understanding the two-loop challenge, we use a $D$-dimensional color-dual bootstrap to successfully construct globally color-dual local two-loop four-point nonlinear sigma model (NLSM) numerators. The double-copy of these NLSM numerators with themselves, pure Yang-Mills, and $\mathcal{N}=4$ super-Yang-Mills correctly reproduce the known unitarity constructed integrands of special Galileons, Born-Infeld theory, and Dirac-Born-Infeld-Volkov-Akulov theory, respectively. Applying our bootstrap to two-loop four-point pure Yang-Mills, we exhaustively search the space of local numerators and find that it fails to satisfy global color-kinematics duality, completing a search previously initiated in the literature. We pinpoint the failure to the bowtie unitarity cut, and discuss a path forward towards non-local construction of color-dual integrands at generic loop order.Comment: 42 pages, 4 figures, ancillary fil

Graffiti, postgraffiti y reconfiguración urbana: usos sociales de las gráficas públicas en el mercado popular de San Roque y en el barrio La Floresta

El creciente protagonismo de las expresiones gráficas públicas del postgraffiti y el graffiti en la transformación de las ciudades, en el marco del actual reordenamiento urbano, viene acompañado de la paulatina institucionalización, profesionalización y regulación de estas prácticas. Esta investigación desarrolla un análisis comparativo de los usos sociales múltiples que adquirieron las piezas de postgraffiti y graffiti en tres festivales de gráfica pública, realizados en dos espacios sociales de la ciudad andina de Quito (el barrio La Floresta y el Mercado de San Roque), durante el periodo 2014-2019. La importancia de analizar la gráfica pública en estos dos espacios sociales radica en que se puede rastrear los distintos matices que adquirieron los usos de la gráfica a través de la diferencia en la trama de condiciones espaciales, económicas, políticas y socioculturales, así como, en las necesidades o intereses de quienes propiciaron la producción de las gráficas y de quienes se apropiaron de las mismas

Caracterización de las propiedades físicas y químicas de la madera de cinco especies forestales procedentes de la parroquia Multitud, cantón Alausí, provincia de Chimborazo.

El objetivo de la investigación fue el de caracterizar las propiedades físicas y químicas de la madera de cinco especies forestales procedentes de la parroquia Multitud, cantón Alausí, provincia de Chimborazo, para lo cual se colectó muestras dendrológicas fértiles y maderas. La tipificación taxonómica de las especies se realizó en el herbario de la Escuela Superior Politécnica de Chimborazo. Las propiedades físicas caracterizadas fueron: anatómicas, organolépticas y densidad. La propiedad química caracterizada fue, el pH de las maderas. Para la caracterización anatómica se utilizó tejidos finos de madera de 2x2 cm, tintes Astrablue (A), Safranina (S), mezcla (S/A) y la lista IAWA. La caracterización organoléptica se realizó según los lineamientos de las normas COPANT y a través de órganos Sensoriales. Las densidades de las maderas, tanto en estado seco y verde, se determinó, usando cubos de madera y aplicando la fórmula de la densidad. El pH de las maderas se caracterizó, utilizando una solución de aserrín-agua destilada y el uso de un pH metro. Como resultados, los nombres científicos de las cinco especies corresponden a Clusia multiflora, Erythrina edulis, Myrcia fallax, Nectandra membranacea y Ruagea pubescens. Las maderas de todas las especies presentan características anatómicas como: parénquima, radios, fibras, fibrotraqueidas, entre otros. Los análisis estadísticos mostraron que las características anatómicas tienen diferencias significativas entre especies. En todas las maderas se observó características organolépticas como: color, olor, grano, brillo, veteado, textura y sabor. Las densidades de las maderas en estado seco y verde se sitúan dentro del rango 0,38 g/cm3 a 0,75 g/cm3 y 0,69 g/cm3 a 0,99 g/cm3 respectivamente. El pH de 4 maderas es ligeramente acida y una madera es de pH neutro. En conclusión, las especies pertenecen a diferentes familias y las características físicas químicas de sus maderas son diferentes en al menos una.The aim of the research was to characterize the physical and chemical properties of the wood of five forest species from Multitud parish, Alausí canton, Chimborazo province. Chimborazo, so that fertile dendrological samples and woods were collected. The typological taxonomy of the species was carried out in the herbarium of the Escuela Superior Politécnica de Chimborazo. Chimborazo. The physical properties characterized were: anatomical, organoleptic and density. The chemical property categorized was the pH of the woods. For the anatomical characterization were used 2x2 cm thin wood tissues, Astrablue (A), Safranina (S), mixture (S/A) and the IAWA list. IAWA LIST. The organoleptic characterization was carried out according to the guidelines of the COPANT standards and through sensory organs, through sensory organs. The densities of the woods, both in the dry and green state, were determined using wood cubes. The pH of the woods was characterized using a sawdust-distilled water solution and the use of a pH meter. As a result, the scientific names of the five species correspond to Clusia multiflora, Erythrina edulis, Myrcia falla, Nectandra membranacea and Ruagea pubescens. The woods of all the species show anatomical species present anatomical characteristics such as: parenchyma, rays, fibers, fibrotracheids, among others. Statistical analyses showed that the anatomical characteristics have significant differences between species. In all the woods organoleptic characteristics were observed such as: color, odor, grain, brightness, grain, texture and flavor. The densities of the woods in the dry and green states woods were in the range 0.38 g/cm3 to 0.75 g/cm3 and 0.69 g/cm3 to 0.99 g/cm3 respectively. The pH of 4 woods is slightly acid and one wood has a neutral pH. In conclusion, the species belong to different families and the chemical physical characteristics of their woods are different in at least one

Perfecting one-loop BCJ numerators in SYM and supergravity

We take a major step towards computing $D$-dimensional one-loop amplitudes in general gauge theories, compatible with the principles of unitarity and the color-kinematics duality. For $n$-point amplitudes with either supersymmetry multiplets or generic non-supersymmetric matter in the loop, simple all-multiplicity expressions are obtained for the maximal cuts of kinematic numerators of $n$-gon diagrams. At $n=6,7$ points with maximal supersymmetry, we extend the cubic-diagram numerators to encode all contact terms, and thus solve the long-standing problem of \emph{simultaneously} realizing the following properties: color-kinematics duality, manifest locality, optimal power counting of loop momenta, quadratic rather than linearized Feynman propagators, compatibility with double copy as well as all graph symmetries. Color-kinematics dual representations with similar properties are presented in the half-maximally supersymmetric case at $n=4,5$ points. The resulting gauge-theory integrands and their supergravity counterparts obtained from the double copy are checked to reproduce the expected ultraviolet divergences.Comment: 55 pages; Dedicated to the memory of Lars Brin

Evaluación a escala de planta piloto del proceso industrial para la obtención de aceite esencial de cardamomo, bajo la filosofía “cero emisiones"

This study describes a simple and economic method for the extraction of essential oils under zero emissions philosophy. The design and operation of the equipment is presented. The results showed the possibility of get a 5% yield of the essential oil of cardamom seeds, which is in agreement with the bibliography.El presente estudio describe un método simple y económico para la extracción de aceites esenciales bajo la filosofía “Cero Emisiones”. Se presenta el diseño y funcionamiento del equipo. Los resultados mostraron la posibilidad de obtener un rendimiento de aceite esencial de cardamomo del 5%, dato que concuerda con el reportado por la literatura

Digital readiness in 3D bioprinting: software, governance and hospitals’ proto-clinical interfaces

Aim: To understand the process through which some hospitals have become ready to assimilate the digital technologies required for 3D bioprinting. By enhancing their digital readiness, hospitals will be able to develop the current proto-clinical potentialities of bioprinting. Materials & methods: We conducted interviews with bioprinting researchers, entrepreneurs and regulators in three countries (United Kingdom, Italy and Brazil). We analyzed bioprinting papers in which hospital-based researchers participated. We also analyzed the international bioprinting market. Results: Digital readiness is more advanced in some hospitals and countries, which have noticed the strategic relevance of bioprinting. Furthermore, it is strengthened by the reformulation of the relations between hospitals and other institutions, a phenomenon that is here interpreted with the concept of interfaces

Diseño de un sistema de fabricación de cabinas de protección para conductores de vehículos de transporte público.

Proyecto orientado a diseñar un sistema de fabricación de cabinas de protección resistentes y funcionales para los conductores del transporte público, mediante el uso de materiales que cumplan con esta doble función, disminuir los riesgos de contagios por el COVID 19 y salvaguardarlos del ataque no deseado de personas que puedan atentar contra su integridad, se plantea el diseño de una máquina dobladora de láminas (como equipo principal) que permita procesar y desarrollar un tipo de cabina para los diferentes automotores en el mercado ecuatoriano