Asymptotic structure of the Einstein-Maxwell theory on AdS3_{3}

The asymptotic structure of AdS spacetimes in the context of General Relativity coupled to the Maxwell field in three spacetime dimensions is analyzed. Although the fall-off of the fields is relaxed with respect to that of Brown and Henneaux, the variation of the canonical generators associated to the asymptotic Killing vectors can be shown to be finite once required to span the Lie derivative of the fields. The corresponding surface integrals then acquire explicit contributions from the electromagnetic field, and become well-defined provided they fulfill suitable integrability conditions, implying that the leading terms of the asymptotic form of the electromagnetic field are functionally related. Consequently, for a generic choice of boundary conditions, the asymptotic symmetries are broken down to $\mathbb{R}\otimes U\left(1\right)\otimes U\left(1\right)$. Nonetheless, requiring compatibility of the boundary conditions with one of the asymptotic Virasoro symmetries, singles out the set to be characterized by an arbitrary function of a single variable, whose precise form depends on the choice of the chiral copy. Remarkably, requiring the asymptotic symmetries to contain the full conformal group selects a very special set of boundary conditions that is labeled by a unique constant parameter, so that the algebra of the canonical generators is given by the direct sum of two copies of the Virasoro algebra with the standard central extension and $U\left(1\right)$. This special set of boundary conditions makes the energy spectrum of electrically charged rotating black holes to be well-behaved.Comment: 18 pages, no figure

Seismic performance of Chilean concentrically braced frame industrial structures: effects of recent code modifications

Few seismic design codes for industrial structures exist worldwide. Among them, the Chilean design code was put to the test by the Maule earthquake of 2010, one of the largest seismic events in recent years. Although the seismic performance of industrial steel structures designed under these provisions was satisfactory, the standard was revised based on the accumulated evidence on the performance after the event and the advances in seismic design since the code was released in 2003. The revision process led to a number of modifications to the provisions, including those for structures based on concentrically braced frames (CBFs), a structural typology widely used in the industry. The modifications, mainly aimed at improving seismic performance in severe events, ranged from the seismic demand to the provisions for sizing structural elements and connections. This work evaluates the effect of these modifications on the design and seismic performance of CBFs. For this purpose, six industrial steel structures were designed using the current standard and the proposed version. The performance was evaluated through static non-linear analyses in 3D models according to the methodology prescribed by the FEMA P695 standard. The models included the non-linearity of braces, columns, beams or struts, and anchor bolts. The results showed similar performance between the structures designed using the proposed and the current version of the standard, in terms of overstrength and response modification factors. However, the performance improved when comparing the maximum drift that the structures can reach and the energy levels they are able to accumulate at these drifts. In terms of the cost–performance ratio, the improvement in performance is associated with moderate increases in cost

Family Arrangements and Quality of Life in Mexican Patients with Dementia

Introduction: In the aging population, especially in subjects with dementia, the degree of dependence increases, as well as an increase in the needs of health services and social costs of care. The family is the main support network for a dependent older person. However, it leads to a different family structure. Objective: To determine the influence of the types of arrangements of the caregiver family on the quality of life of the patient with dementia. Method: Observational and cross-sectional study. Patients older than 65 years with dementia were included. The family arrangement and the quality of life of the patients, and the caregiver, were identified. The type of family arrangement was classified according to The Savvy Caregiver Trainer's Manual, and quality of life was measured using the Quality of Life in Alzheimer's disease [QOL-AD] scale. Results: 200 patients with dementia and their main caregivers were included. The patients' median age was 80 [73-84] years, 125 [62.5%] women. The main family arrangement identified was the solitary caregiver [51.5%], followed by the collaborative caregiver [25.5%] and sequential caregiver [19%]. We found a lower score on the QOL-AD scale in patients with global intermediate phase dementia and patients with a solitary caregiver and collaborative caregiver compared to those in the initial phase. We found no difference in the score between the different types of caregivers globally or each phase of dementia. Conclusion: The type of family arrangement that the patient has does not influence the caregiver's quality of life or dementia. However, physicians can make a family focus on other factors related to a decrease in family burden

Association between 24-h movement guidelines and cardiometabolic health in Chilean adults

© The Author(s) 2022. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.This study aimed to examine the association between meeting 24-h movement guidelines and cardiometabolic health in Chilean adults. We used cross-sectional data of 2618 adults from the Chilean National Health Survey 2016-2017. Meeting the 24-h movement guidelines was defined as ≥ 600 MET-min/week of physical activity; ≤ 8 h/day of sitting time; and 7 to 9 h/day of sleep duration. Cardiometabolic health indicators were body mass index, waist circumference, high triglycerides, high blood pressure, type 2 diabetes, metabolic syndrome, and risk of cardiovascular disease in a 10-year period. Meeting none out of three 24-h movement guidelines (vs all three) was associated with higher odds of overweight/obesity (OR 1.67; 95%CI 1.45 to 1.89), high waist circumference (1.65; 1.40 to 1.90), hypertension (2.88; 2.23 to 3.53), type 2 diabetes (1.60; 1.26 to 1.94), metabolic syndrome (1.97; 1.54 to 2.40) and risk of cardiovascular disease (1.50; 1.20, 1.80). Meeting one guideline (vs three) was associated with higher odds of five of out seven cardiometabolic indicators. Our study found that the composition of movement behaviors within a 24-h period may have important implications for cardiometabolic health.info:eu-repo/semantics/publishedVersio

Stability Assessment of Rock Slopes Using the Q-Slope Classification System: A Reliability Analysis Employing Case Studies in Ecuador

Q-slope is one of the most recent empirical geomechanical classification systems and the least studied in South America. This study aims to expand the knowledge base regarding the Q-slope geomechanical method and demonstrate its applicability and reliability in rock slopes of Andean countries, such as Ecuador. To this end, thirty rocky slopes have been characterized considering (1) the physical visual approach—geographic location, climate, lithology, alteration, and stability (to obtain values of Jr, Ja, Jwice, and SRFa)—and (2) geomechanical stations and kinematic analysis (for the determination of the type of failure, Jn, O-factor, and SRFc for Q-slope). Field data were collected in contrasting environments (coastal, mountain, and forest), and different failure modes were considered (planar, wedge, block, and flexural topplings) to better understand the method. The results and main contributions of this research are (i) verifying the applicability of the Jwice parameters in different climatic settings and (ii) validating the Q-slope method by applying a confusion matrix to evaluate its reliability for slope stability assessment. The overall accuracy obtained is 80%, placing the Q-slope geomechanical method in the highest evaluation quartile and thus classifying it as very good for slope characterization.This work was partially funded by the University of Alicante (vigrob-157 project), the Prometheus Project of the Secretariat of Higher Education, Science, Technology and Innovation of the Republic of Ecuador (for field data acquisition from 2014 to 2015), FCI Projects at the Faculty of Natural Sciences of University of Guayaquil, and by Conselleria de Innovación, Universidades, Ciencia y Sociedad Digital in the framework of the project CIAICO/2021/335

Representaciones mentales y enfermedades crónicas: un análisis de la escala causas del cuestionario IPQ en pacientes con hipertensión arterial y diabetes

89 p.El objetivo de esta investigación fue abordar las representaciones mentales en relación a las enfermedades crónicas, analizando la escala causas del cuestionario de percepción de la enfermedad IPQ en pacientes con hipertensión arterial y diabetes. Además se exploró la relación con otras variables como sexo, edad y nivel educacional. Se realizó un análisis de la base de datos obtenida de la aplicación del instrumento en cinco centros de salud de atención primaria de la séptima y octava región, obteniéndose una muestra total de 313 participantes, de los cuales 210 tienen hipertensión arterial y 103 tienen diabetes. Se realizó una comparación de medias de cada ítem según enfermedad crónica padecida, además de la correlación de estos con tres variables demográficas. Por otra parte se clasificaron los ítems de la escala según la dimensión Locus de control (Interno/Externo). Se obtuvo que la escala causas presenta 13 atribuciones causales con diferencias significativas según el tipo de enfermedad crónica padecida. Los mayores puntajes se encontraron en el grupo de pacientes con hipertensión arterial. En cuanto al análisis de variables demográficas, se encuentran relaciones significativas para las tres variables analizadas. Finalmente, en relación a la clasificación de las atribuciones causales de la enfermedad según dimensión, los ítems son clasificados en mayor proporción en locus de control interno. Se reconoce la necesidad de continuar investigando esta temática con el fin de ampliar estos resultados dado que son relevantes debido al efecto que tienen sobre la adherencia al tratamiento que desplieguen los pacientes. Palabras clave: Enfermedades crónicas, atribuciones causales, comparación de medias./ABSTRACT: The objective of this research was to approach mental representations related to chronic diseases analyzing the causes scale of the illness perception questionnaire IPQ in patients with hypertension and diabetes. We also explored the relationship with other variables like gender, age and educational level. An analysis of the database obtained from the application of the instrument in five health centers of primary care of the seventh and eight regions was made, yielding a total sample of 313 participants, of whom 210 have hypertension and 103 have diabetes. A comparison of means was made for each item according to the suffered chronic disease, besides the correlation of this three with the demographic variables. On the other hand the items of the scale were classified according to the locus of control dimension (internal/external). It was obtained that the scale causes has 13 causal attributions with significant differences depending on the type of suffered chronic disease. The highest scores were found in the hypertension patients group. In the analysis of demographic variables, significant relationships were found for the three variables analyzed. Finally, regarding to the classification of the causal attributions of the disease by dimension, the items were classified in a higher proportion for internal locus of control. Is recognized the need to continuing researching this issue in order to extend these results which are relevant due to the effect that has over the adherence to treatment that display patients. Key words: Chronic diseases, causal attributions, comparison of means

Prevalencia de caries en niños de 6 años en la comuna de San Pedro de Atacama

Objective: To assess the prevalence of Caries in 6-year-old children of San Pedro of Atacama commune in 2019.   Material and methods: An observational cross-sectional study was conducted from January to December 2019 in which 6-year-old children from the E-26 school in San Pedro of Atacama and schools in the nearby towns of the commune were examined. All examinations were performed by the same operator using the ICDAS scale. Parents were asked for informed consent before the clinical dental examination took place. The data obtained were analyzed using the Stata v.15 statistical program. Results: There was a statistically significant difference (p <0.005) found between both surveys, with an increase of correct answers in the second survey. Conclusion: The prevalence of caries in 6-year-old children in the commune of San Pedro of Atacama is high, therefore, the efforts of the dental team should be centered on education and oral hygiene instruction of children, parents, and teachers.Objetivo: Consiste en determinar la prevalencia de caries en niños de 6 años en la comuna de San Pedro de Atacama en el año 2019. Materiales y métodos: Se realizó un estudio observacional de corte transversal desde enero a diciembre del año 2019 en donde se examinaron a los niños de 6 años de la escuela E-26 de San Pedro de Atacama y escuelas de las localidades del interior de la comuna como Peine, Socaire y Toconao. Todos los niños fueron examinados por un mismo operador utilizando escala ICDAS. A los padres se les entrego consentimiento informado para poder realizar el examen clínico odontológico. Los datos obtenidos y análisis de estos se realizaron con programa estadístico Stata v.15.Resultados: El análisis de los resultados demuestra que existe una diferencia estadísticamente significativa (p<0.005) entre ambas encuestas, con un aumento de respuestas correctas en la segunda encuesta. Conclusión: La prevalencia de caries en niños de 6 años en la comuna de San Pedro de Atacama es alta y se deben orientar los esfuerzos del equipo Odontológico en educación e instrucción higiene oral de los niños, padres y profesores

A Binary Fruit Fly Optimization Algorithm to Solve the Set Covering Problem

The Set Covering Problem (SCP) is a well known NP-hard problem with many practical applications. In this work binary fruit fly optimization algorithms (bFFOA) were used to solve this problem using different binarization methods. The bFFOA is based on the food finding behavior of the fruit flies using osphresis and vision. The experimental results show the effectiveness of our algorithms producing competitive results when solve the benchmarks of SCP from the OR-Library