Multivariate Bayesian semiparametric models for authentication of food and beverages

Food and beverage authentication is the process by which foods or beverages are verified as complying with its label description, for example, verifying if the denomination of origin of an olive oil bottle is correct or if the variety of a certain bottle of wine matches its label description. The common way to deal with an authentication process is to measure a number of attributes on samples of food and then use these as input for a classification problem. Our motivation stems from data consisting of measurements of nine chemical compounds denominated Anthocyanins, obtained from samples of Chilean red wines of grape varieties Cabernet Sauvignon, Merlot and Carm\'{e}n\`{e}re. We consider a model-based approach to authentication through a semiparametric multivariate hierarchical linear mixed model for the mean responses, and covariance matrices that are specific to the classification categories. Specifically, we propose a model of the ANOVA-DDP type, which takes advantage of the fact that the available covariates are discrete in nature. The results suggest that the model performs well compared to other parametric alternatives. This is also corroborated by application to simulated data.Comment: Published in at http://dx.doi.org/10.1214/11-AOAS492 the Annals of Applied Statistics (http://www.imstat.org/aoas/) by the Institute of Mathematical Statistics (http://www.imstat.org

Use of informal mobile telephony in low income households in Colombia

Access to mobile telephony in Colombia exhibits rather interesting features compared to other countries. Colombia witnessed the beginning of a new alternative for communication consisting in the use of informal resale of minutes on the streets and small stores during the first years of this century. In this paper we are interested in analyzing the main factors that determine the utilization of this kind of service. We use a probabilistic model to explain the characteristics of the people that use `informal resale´ on the streets and we find that people in the modality of prepayment and people from small cities has a higher probability of using this alternative. It is also found that people in the firm-leader use more often this service. These results seem indicate that price differentials among on-net and off-net and between prepaid and postpaid are the causes of the rise of this economic activity.***El acceso a la telefonía móvil en Colombia evidencia ciertas particularidades con respecto a otros países. En Colombia surgió una nueva alternativa de comunicación que consistía en la venta de minutos de celular en las calles y en pequeños negocios durante los primeros años de ésta década. En este documento se analizan las principales características de quienes usan esta modalidad de comunicación con base en una encuesta dirigida a usuarios y no usuarios de bajos ingresos. Se usa un modelo probabilístico para explicar las características de las personas que lo usan y se encuentra que las personas que están en la modalidad de contrato prepago y que viven en ciudades pequeñas tienen una mayor probabilidad de usar esta alternativa de comunicación. De otro lado se encuentra que quienes están con el operador dominante tienden a usar este servicio también de una forma más notoria. Estos resultados parecen indicar que los diferenciales de precios entre las llamadas off-net y on-net así como entre prepago y postpago son los que alimentaron el surgimiento de esta actividad.Mobile telephony, ICT, gender gap, Resale

Low weight additive manufacturing FBG accelerometer: design, characterization and testing

Structural Health Monitoring is considered the process of damage detection and structural characterization by any type of on-board sensors. Fibre Bragg Gratings (FBG) are increasing their popularity due to their many advantages like easy multiplexing, negligible weight and size, high sensitivity, inert to electromagnetic fields, etc. FBGs allow obtaining directly strain and temperature, and other magnitudes can also be measured by the adaptation of the Bragg condition. In particular, the acceleration is of special importance for dynamic analysis. In this work, a low weight accelerometer has been developed using a FBG. It consists in a hexagonal lattice hollow cylinder designed with a resonance frequency above 500 Hz. A Finite Element Model (FEM) was used to analyse dynamic behaviour of the sensor. Then, it was modelled in a CAD software and exported to additive manufacturing machines. Finally, a characterization test campaign was carried out obtaining a sensitivity of 19.65 pm/g. As a case study, this paper presents the experimental modal analysis of the wing of an Unmanned Aerial Vehicle. The measurements from piezoelectric, MEMS accelerometers, embedded FBGs sensors and the developed FBG accelerometer are compared.Ministerio de Economía y Competitividad BIA2013-43085-P y BIA2016-75042-C2-1-

‘I will stay here’: public space and social inequality during the COVID-19 pandemic

The implementation of city lockdowns in response to the COVID-19 pandemic exposed some social inequalities in Mexico. The paper evaluates the effects of the closure of the Alameda Central, a public park in the Historic Centre of Mexico City. It examines how its closure affected some vulnerable populations, including homeless people, beggars, street vendors, buskers, and male sex workers, to the extent that they resisted leaving or found ways to return to public space. The research shows how Mexican COVID-19 policies tended to overlook the diversity of populations making use of public space, and their various necessities

Un castellano en la corte de Enrique III de Inglaterra :: relaciones entre la escuela de Salamanca y el circulo cortesano de Westminster

Las pinturas murales del muro oriental de la capilla de San Martín de la catedral vieja de Salamanca presentan una inscripción que indica su autoría por parte de Antón Sánchez de Segovia y su fecha de ejecución: 1262. Esta fecha resulta sorprendente, pues sus rasgos estilísticos manifiestan un conocimiento íntimo de las innovaciones del arte francés e inglés de los años cincuenta del siglo XIII, exigiendo, en consecuencia, la formación de su autor en un medio al tanto de estas innovaciones. Nuevas aportaciones sobre Peter of Spain, pintor documentado al servicio de Enrique III de Inglaterra entre 1251 y 1262, permiten sugerir que acaso fuera él el enlace que hizo posible esta singular creación.The paintings on the east wall of the chapel of San Martín of the Old Cathedral of Salamanca show an inscription which records both their authorship by Antón Sánchez de Segovia and their date of execution: 1262. Such a date is surprising, as their stylistic features prove a close acquaintance of the novelties of the French and English art of the 1250s and, consequently, require the training of their author in a milieu aware of these novelties. New light into the records concerning Peter of Spain, a painter recorded in the service of king Henry III of England between 1251 and 1262, allows to suggest that maybe he was the link who made possible such a singular creation

Pre-investigation of water electrolysis for flexible energy storage at large scales: the case of the Spanish power system

This report analyzes the basis of hydrogen and power integration strategies, by using water electrolysis processes as a means of flexible energy storage at large scales

Panorama del arte cristiano actual en India, China y Japón

En este trabajo se hace un recorrido por el panorama artístico contemporáneo vinculado a la difusión del Cristianismo en China, India y Japón durante el siglo XX. Se estudian sus principales creadores, sus obras más singulares y se profundiza en una estética donde el arte cristiano asume la tradición cultural de estos países

Hábitos de lectura en pantalla y bibliotecas en Argentina: un cruce todavía inexplorado e inesperado

The National Reading Council held a "National Survey on the reading habits of 2011" in Argentina. The results were published last year with all the bubbles from the national government although the mass media gave little coverage to it. Since then and with the "juicy" report I have been several reflections have led me to wonder mainly about the place you occupy libraries before reading digital and screen in Argentina (although the reflections could be extrapolated to other latitudes)

El sepulcro de doña María Ruiz de Tosantosun conjunto de estilo gótico lineal tardío en la iglesia parroquial de Castilseco (La Rioja)

Producción CientíficaLos trabajos de restauración efectuados en 2008-10 en la iglesia parroquial de San Julián de la pequeña localidad de Castilseco (La Rioja) pusieron al descubierto un conjunto de pinturas murales medievales. A partir de la epigrafía existente en las propias pinturas murales y de la documentación del cercano monasterio jerónimo de San Miguel del Monte, ya desaparecido, es posible identificar este conjunto, que se localiza en el muro meridional del presbiterio de la iglesia, dentro y alrededor de un arcosolio apuntado que en su momento albergó un enterramiento, como el sepulcro de doña María Ruiz de Tosantos, que dictó su testamento en 1386 y que pidió que su tumba fuese totalmente pintada. El estudio detallado de las pinturas murales pone de manifiesto que son un ejemplo destacado del estilo gótico lineal en su última fase de desarrollo que puede ser atribuido a un artista de Burgos, dadas la importancia de esta ciudad en este periodo y las características del sepulcro, a relacionar con ejemplares burgaleses.Conservation carried out in 2008-10 in the parish church of San Julián of the small hamlet of Castilseco (La Rioja) brought to light an ensemble of Medieval wall paintings. On the ground of the epigraphy displayed on the wall paintings themselves and of the records from the now disappeared nearby Hieronymite monastery of San Miguel del Monte, it is possible identifying this ensemble, located in the south wall of the presbytery of the church, inside and around a pointed niche that once housed a burial, as the tomb of doña María Ruiz de Tosantos, who dictated her will in 1386 ordering her tomb to be fully painted. A close analysis of the wall paintings reveals that they are an outstanding example of the linear Gothic style in its last phase of development that can be attributed to an artist from Burgos, given the prominence of this city in this period and the features of the tomb, which can be related to specimens from Burgos