606 research outputs found
Estimating mobility of tourists. New Twitter-based procedure
Twitter has been actively researched as a human mobility proxy. Tweets can contain two classes of geographical metadata: the location from which a tweet was published, and the place where the tweet is estimated to have been published. Nevertheless, Twitter also presents tweets without any geographical metadata when querying for tweets on a specific location. This study presents a methodology which includes an algorithm for estimating the geographical coordinates to tweets for which Twitter doesn't assign any. Our objective is to determine the origin and the route that a tourist followed, even if Twitter doesn't return geographically identified data. This is carried out through geographical searches of tweets inside a defined area. Once a tweet is found inside an area, but its metadata contains no explicit geographical coordinates, its coordinates are estimated by iteratively performing geographical searches, with a decreasing geographical searching radius. This algorithm was tested in two touristic villages of Madrid (Spain) and a major city in Canada. A set of tweets without geographical coordinates in these areas were found and processed. The coordinates of a subset of them were successfully estimated.Agencia Estatal de Investigación | Ref. PID2020-116040RB-I00Universidade de Vigo/CISU
Ecology and land arrangement: the case of Murcia city and surroundings II. Diagnosis and impacts evaluation
Este trabajo constituye la segunda parte del estudio ecológico integrado de la aglomeración
urbana de Murcia y su área de influencia. Se describen y desarrollan las fases de diagnosis y evaluación de impactos.
Los resultados obtenidos ponen de manifiesto la eficacia del sistema utilizado, examinándose
en detalle su aplicación en proyectos de planeamiento territorial.
Destacan como recomendaciones generales aquéllas relativas al crecimiento industrial y urbano;
desarrollo de áreas residenciales y su localización; control de vertidos al Río Segura; tratamiento
de reforestación de cabeceras y márgenes de ramblas; creación de parques urbanos rurales y gradación
de medidas de protección de lo que debería ser el Parque Regional del municipio de Murcia
y alrededores, la denominada «costera sur».This work summarizes the second part of the integrated ecological study of the urban aglomeration
of Murcia and its surroundings. The phases of impact diagnosis and evaluation are described
and expanded.The results obtained expose the efficiency of the system used, and its application in the field
of land planning projects is examined in detail.
The recomendations which stand out most are those which refer to urban and industrial growth;
those related to the progress and emplacement of residential areas; the control of effluent in the
Segura River;the afforestation of headwaters («cabeceras») and dry river bed («ramblas») banks;
the creation of urban parks and the adoption of protective measures of what should be the Regional
Park of Murcia Municipality and its surrounding area, the so-called «costera sur»
Importancia según la evidencia actual: Esquema de Oclusión lateral y trastornos temporomandibulares. Revisión bibliográfica
Objective: To review the relationship between lateral occlusion patterns and temporomandibular disorders (TMDD) in the scientific literature. Materials and Method: A search was performed in PubMed and EBSCO databases, using keywords occlusion, canine guide, temporomandibular disorders, and clinical evidence; selecting 15 of 65 papers in English published in the last five years: literature and systematic reviews, control, cohort and clinical cases in permanent dentition, occlusal alterations and TMDD. Those studies that were not literary or systematic reviews, cohort, controls, or clinical cases in children under 18 years of age or primary dentition were excluded. Results: TMDD is multifactorial, although infrequently there is only one factor involved. To link just occlusion and TMDD is precipitous. Lateral occlusal patterns are influenced by mandibular excursion, age, and static occlusal relationship, in 73% of the articles. There is no relationship between lateral occlusion patterns and the development of TMDD, but there is an association with mediotrusive interferences (5%), although, this does not imply that these cause TMDD, but sequelae. 70-80% of TMDD respond to nonspecific treatments.The canine guide was found to be progressively modified with advancing age, being replaced by group function. Teething can be restored with different schemes. 53% of reviewed studies condemned total mechanical approaches in TMDD with irreversible occlusal treatments (orthodontics, prosthodontics, occlusal adjustment). For 80%, altering occlusal patterns to prevent or treat only TMDD was inadmissible. Conclusion: There is no solid relationship between occlusion and TMDD. With an interdisciplinary team, future research should focus less on dental occlusion and more on factors such as pathophysiological, psychosocial, and cultural related to TMDD.Objetivo: Revisar en literatura científica la relación entre esquemas de oclusión lateral y transtornos temporomandibulares (TTMD). Objetivos específicos: Identificar la relación multifactorial de TTMD en distintos esquemas oclusivos laterales; Explicar la relación entre tratamientos irreversibles oclusales y TTMD.Materiales y Métodos: Búsqueda en PubMed y EBSCO desde 2015, utilizando palabras claves: occlusion, canine guide, temporomandibular disorders, clinical evidence; seleccionando 15 de 65 trabajos en inglés: revisiones de literatura y sistemáticas, casos control, cohorte y clínicos en dentición permanente, alteraciones oclusales y TTMD, con comparación objetiva del tratamiento bajo seguimiento clínico. Exclusión de trabajos que no fueran revisiones literarias o sistemáticas, casos cohorte, control, ni clínicos en menores de 18 años o dentición temporal.Resultados: Los TTMD son multifactoriales, infrecuentemente hay un solo factor. Vincular solo oclusión y TTMD es precipitado. Esquemas oclusales laterales están influenciados por: excursión mandibular, edad y relación oclusal estática, en 73% de los artículos. No hay relación entre esquemas de oclusión lateral y desarrollo de TTMD. Solo interferencias mediotrusivas están asociadas (5%), esto no implica que causen TTMD, son secuelas. El 70-80% de TTMD responden a tratamientos inespecíficos. Anormalidades como clicks articulares disminuyen, además el dolor crónico en TTMD tiene relación con sensibilización central. La guía canina se modifica progresivamente con el avance de edad, siendo reemplazada por función grupal. Desviar estándares oclusivos laterales no significa tener oclusión no fisiológica, oclusión ideal rara vez se observa. Se puede restaurar dentición con diferentes esquemas. El 53% condena enfoques totalmente mecánicos en TTMD con tratamientos oclusales irreversibles (ortodoncia, prostodoncia, ajuste oclusal). Para el 80%, alterar esquemas oclusales en prevenir o tratar únicamente TTMD es inadmisible.Conclusión: No hay relación sólida entre oclusión y TTMD. Con equipo interdisciplinario, futuras investigaciones deben centrarse menos en oclusión dental y más en factores: fisiopatológicos, psicosociales y culturales relacionados a TTMD
Análisis comparado de fuentes de financiación de una empresa real
El sector de la construcción, y más concretamente la actividad inmobiliaria, ha sido el sector más afectado tras la llegada de la crisis económica en el año 2007. Es por ello por lo que se ha elegido una empresa perteneciente a este sector, realizando un análisis económico-financiero en el periodo comprendido entre los años 2006 y 2013. Este periodo se ha elegido con el fin de apreciar cómo la sociedad se ha visto afectada tras la recesión económica de España, además de haber entrado ésta en concurso de acreedores en 2013. Por otra parte, la estructura financiera de la empresa presenta unas características particulares por el hecho de ser una empresa constructora. Con el propósito de llevar a cabo un estudio de la misma, se realizará un análisis de las diferentes fuentes de financiación y, posteriormente, se observarán cuáles son de aplicación en el sector de la construcción. Finalmente, se distinguirán los métodos de financiación de la empresa objeto de estudio, realizándose una posterior comparativa con la herramienta más utilizada en el sector llamada Project Finance. Palabras clave: sector construcción, crisis, análisis, fuentes de financiación, Project Financ
Grape epicatechin conjugates prevent erythrocyte membrane protein oxidation
Epicatechin conjugates obtained from grape have shown antioxidant activity in various systems. However, how these conjugates exert their antioxidant benefits has not been widely studied. We assessed the activity of epicatechin and epicatechin conjugates on the erythrocyte membrane in the presence and absence of a peroxyl radical initiator, to increase our understanding of their mechanisms. Thus, we studied cell membrane fluidity by fluorescence anisotropy measurements, morphology of erythrocytes by scanning electron microscopy, and finally, red cell membrane proteins by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Our data showed that incubation of red cells in the presence of epicatechin derivatives altered membrane fluidity and erythrocyte morphology but not the membrane protein pattern. The presence in the medium of the peroxyl radical initiator 2,2′-azobis(amidinopropane) dihydrochloride (AAPH) resulted in membrane disruptions at all levels analyzed, causing changes in membrane fluidity, cell morphology, and protein degradation. The presence of antioxidants avoided protein oxidation, indicating that the interaction of epicatechin conjugates with the lipid bilayer might reduce the accessibility of AAPH to membranes, which could explain in part the inhibitory ability of these compounds against hemolysis induced by peroxidative insult
Numerical Simulation of a Wall-Flow Particulate Filter Made of Biomorphic Silicon Carbide Able to Fit Different Fuel/Biofuel Inputs
To meet the increasingly strict emission limits imposed by regulations, internal combustion
engines for transport applications require the urgent development of novel emission abatement
systems. The introduction of biodiesel or other biofuels in the engine operation is considered to
reduce greenhouse gas emissions. However, these alternative fuels can affect the performance of the
post-combustion systems due to the variability they introduce in the exhaust particle distribution and
their particular physical properties. Bioceramic materials made from vegetal waste are characterized
by having an orthotropic hierarchical microstructure, which can be tailored in some way to optimize the
filtration mechanisms as a function of the particle distribution of the combustion gases. Consequently,
they can be good candidates to cope with the variability that new biofuel blends introduce in the
engine operation. The objective of this work is to predict the filtration performance of a wall-flow
particulate filter (DPF) made of biomorphic silicon carbide (bioSiC) with a systematic procedure
that allows to eventually fit different fuel inputs. For this purpose; a well-validated DPF model
available as commercial software has been chosen and adapted to the specific microstructural features
of bioSiC. Fitting the specific filtration and permeability parameters of this biomaterial into the
model; the filtration efficiency and pressure drop of the filter are predicted with sufficient accuracy
during the loading test. The results obtained through this study show the potential of this novel DPF
substrate; the material/microstructural design of which can be adapted through the selection of an
optimum precursor.Ministerio de Economía y Competitividad de España (MINECO) MAT2013-41233-RMinisterio de Economía y Competitividad de España (MINECO) BES-2014-069023Ministerio de Economía y Competitividad de España (MINECO) EEBB-I-17-1233
Diseño De Un Sistema Inteligente De Bajo Costo Para Una Edificación Apoyado En Tecnologías Disruptivas
In Casanare, despite the great economic opportunities resulting from the exploitation of hydrocarbons, they do not show great advances related to the application of technologies that guarantee the reasonable use of electrical energy.
More than 70% of the buildings in the department are designed and built under traditional conditions, that is, they do not meet the characteristics of smart housing or home automation, taking into account that the application of disruptive technologies seeks to improve the living conditions of human beings and their environment. .
The implementation of intelligent systems in buildings provides security, protection, communication and comfort, generating a responsible and controlled consumption of resources, the intelligent management of lighting, air conditioning and / or ventilation systems, energy flow, access control, among others. without affecting the internal functions of the building.
With the high rates of energy consumption in homes in rural and urban areas of the different municipalities of the department and with the climatic conditions of the area, the need for the use of intelligent systems is evidenced, promoting the analysis of to what extent the implementation of intelligent systems in buildings guarantee the control, optimization and energy improvement through the use of emerging technologies?En Casanare, a pesar de las grandes oportunidades económicas producto de la explotación de hidrocarburos, no evidencian grandes avances relacionados con la aplicación de tecnologías que garanticen el uso razonable de la energía eléctrica.
Más del 70% de las edificaciones en el departamento están diseñadas y construidas bajo condiciones tradicionales, es decir, que no cumplen características de vivienda inteligente o domótica teniendo em cuenta que la aplicación de tecnologías disruptivas busca mejorar condiciones de vida del ser humano y su entorno.
La implementación de sistemas inteligentes en edificaciones aporta seguridad, protección, comunicación y confort, generando un consumo responsable y controlado de recursos, la gestión inteligente de los sistemas de iluminación, climatización y/o ventilación, flujo energético, control de acceso, entre otros, sin afectar las funciones internas de la edificación.
Con los altos índices de consumo energético en las viviendas del área rural y urbana de los diferentes municipios del departamento y con las condiciones climáticas de la zona se evidencia la necesidad del uso de sistemas inteligentes, promoviendo el análisis de ¿en qué medida la implementación de sistemas inteligentes en edificaciones garantiza el control, optimización y mejoramiento energético por medio del uso de tecnologías emergentes
Tourism-related placeness feature extraction from social media data using machine learning models
The study of placeness has been focus for researchers trying to understand the impact of locations on their surroundings and tourism, the loss of it by globalization and modernization and its effect on tourism, or the characterization of the activities that take place in them. Identifying places that have a high level of placeness can become very valuable when studying social trends and mobility in relation to the space in which the study takes place. Moreover, places can be enriched with dimensions such as the demographics of the individuals visiting such places and the activities the carry in them thanks to social media and modern machine learning and data mining methods. Such information can prove to be useful in fields such as urban planning or tourism as a base for analysis and decision-making or the discovery of new social hotspots or sites rich in cultural heritage.
This manuscript will focus on the methodology to obtain such information, for which data from Instagram is used to feed a set of classification models that will mine demographics from the users based on graphic and textual data from their profiles, gain insight on what they were doing in each of their posts and try to classify that information into any of the categories discovered in this article. The goal of this methodology is to obtain, from social media data, characteristics of visitors to locations as a discovery tool for the tourism industry.Agencia Estatal de Investigación | Ref. PID2020-116040RB-I0
Estado ansioso previo a una evaluación en estudiantes de Odontología
Objetivo: Relacionar el estado ansioso y severidad de ansiedad con el rendimiento académico, previo a una evaluación en estudiantes de tercer año de la Facultad de Odontología, Universidad San Sebastián, sede Concepción, durante el periodo académico 2015. Materiales y método: Estudio exploratorio, transversal analítico. La muestra estuvo constituida por 138 estudiantes de tercer año de la asignatura de Preclínico y Rehabilitación Oral a los cuales se les aplicó el test de Hamilton. Los datos fueron analizados mediante un análisis de varianza de clasificación simple (modelo III) para datos desbalanceados y comparados por la prueba de comparación múltiple de medias deTukey. El nivel de significación fue de α≤0,05. Resultados: Las medias de rendimiento académico y las medias del estado ansioso no difieren entre sí (p = 0,188). El estado ansioso grave muestra un valor menor de rendimiento que las otras clasificaciones. Con respecto al sexo y estado ansioso,estas se distribuyeron por igual entre los sujetos (χ²= 1,57; p=0,21). Conclusiones: De acuerdo a los resultados obtenidos no es posible relacionar directamente el estado ansioso con el rendimiento académico, pero la presencia de ansiedad grave se relaciona conun menoraprovechamiento efectivo
- …