Quasi-Stationary Distributions: Continued Fraction and Chain Sequence Criteria for Recurrence

We study quasi-stationary distributions (q.s.d.) for Markov chains. We review some recent results relating q.s.d. Yaglom limit and limit distributions conditioned to non absorption.

An Empirical Study of Real-World SPARQL Queries

Understanding how users tailor their SPARQL queries is crucial when designing query evaluation engines or fine-tuning RDF stores with performance in mind. In this paper we analyze 3 million real-world SPARQL queries extracted from logs of the DBPedia and SWDF public endpoints. We aim at finding which are the most used language elements both from syntactical and structural perspectives, paying special attention to triple patterns and joins, since they are indeed some of the most expensive SPARQL operations at evaluation phase. We have determined that most of the queries are simple and include few triple patterns and joins, being Subject-Subject, Subject-Object and Object-Object the most common join types. The graph patterns are usually star-shaped and despite triple pattern chains exist, they are generally short.Comment: 1st International Workshop on Usage Analysis and the Web of Data (USEWOD2011) in the 20th International World Wide Web Conference (WWW2011), Hyderabad, India, March 28th, 201

Barreiras de acesso a tratamento para mães com depressão pós-parto em centros de atenção primária: um modelo preditivo

Objective to develop a predictive model to evaluate the factors that modify the access to treatment for Postpartum Depression (PPD). Methods prospective study with mothers who participated in the monitoring of child health in primary care centers. For the initial assessment and during 3 months, it was considered: sociodemographic data, gyneco-obstetric data, data on the services provided, depressive symptoms according to the Edinburgh Postpartum Depression Scale (EPDS) and quality of life according to the Short Form-36 Health Status Questionnaire (SF-36). The diagnosis of depression was made based on MINI. Mothers diagnosed with PPD in the initial evaluation, were followed-up. Results a statistical model was constructed to determine the factors that prevented access to treatment, which consisted of: item 2 of EPDS (OR 0.43, 95%CI: 0.20-0.93) and item 5 (OR 0.48, 95%CI: 0.21-1.09), and previous history of depression treatment (OR 0.26, 95%CI: 0.61-1.06). Area under the ROC curve for the model=0.79; p-value for the Hosmer-Lemershow=0.73. Conclusion it was elaborated a simple, well standardized and accurate profile, which advises that nurses should pay attention to those mothers diagnosed with PPD, presenting low/no anhedonia (item 2 of EPDS), scarce/no panic/fear (item 5 of EPDS), and no history of depression, as it is likely that these women do not initiate treatment.Objetivo desarrollar un modelo predictivo para evaluar los factores que modifiquen el acceso a tratamiento para la DPP. Métodos estudio prospectivo de madres que asistieron a control de niño sano en centros de atención primaria. En evaluación basal y 3 meses, se registraron: datos sociodemográficos, gineco-obstétricos, variables de uso de servicios, síntomas depresivos con la Escala de Depresión Posparto de Edimburgo (EPDS) y calidad de vida con el Cuestionario de Salud SF-36. El diagnóstico de depresión se hizo con el MINI. Se siguió a madres que en evaluación basal tenían DPP. Resultados se construyó un modelo estadístico para determinar los factores que impidieron el acceso a tratamiento, compuesto por: ítems del EPDS 2 (OR 0,43, IC95%: 0,20-0,93) y 5 (OR 0,48, IC95%: 0,21-1,09), e historia previa de tratamiento de depresión (OR 0,26, IC95%: 0,61-1,06). Área bajo la curva ROC para el modelo=0,79; valor de p para la prueba de Hosmer-Lemershow=0,73. Conclusión se elaboró un perfil simple, bien calibrado y discriminante, que sugiere que los/las enfermeros/as estén atentos/as a aquellas madres con DPP que presenten baja/nula anhedonia (ítem 2 EPDS), escaso/nulo pánico/miedo (ítem 5 EPDS), y sin antecedentes de depresión, ya que es probable que estas mujeres no ingresen a tratamiento.Objetivo desenvolver um modelo preditivo para avaliar os fatores que modificam o acesso a tratamento para a DPP. Métodos estudo prospectivo com mães que participaram do acompanhamento da saúde da criança em centros de atenção primária. Na avaliação inicial e durante 3 meses, foram registrados: dados sociodemográficos, gineco-obstétricos, dados sobre o uso dos serviços, sintomas depressivos de acordo com a Escala de Depressão Pós-parto de Edimburgo (EPDS) e qualidade de vida de acordo com o Questionário de Saúde SF-36. O diagnóstico de depressão foi feito com o MINI. Foram acompanhadas as mães que tinham DPP na avaliação inicial. Resultados foi construído um modelo estatístico para determinar os fatores que impediram o acesso a tratamento, constituído por: item 2 da EPDS (OR 0,43, IC95%: 0,20-0,93) e 5 (OR 0,48, IC95%: 0,21-1,09), e história prévia de tratamento para depressão (OR 0,26, IC95%: 0,61-1,06). Área sob a curva ROC para o modelo=0,79; valor de p para o teste de Hosmer-Lemershow=0,73. Conclusão foi elaborado um perfil simples, bem padronizado e preciso, que recomenda que os/as enfermeiros/as estejam atentos/as àquelas mães com DPP que apresentem anedonia baixa/nula (item 2 da EPDS), pânico/medo escasso/nulo (item 5 da EPDS) e sem antecedentes de depressão, já que é provável que estas mulheres não entrem em tratamento

Ten Simple Rules for organizing a non–real-time web conference

The present work describes the 100% virtual ATIDES (Avances en Tecnologı ´as, Innovacio ´n y Desafı ´os de la Educacio ´n Superior) conference that was held between October 15 and 31, 2018, sponsored by Universitat Jaume I (UJI), Spain. Online conferences like this have been the subject of some controversy in the field of education over the last decade. Indeed, we have found a few texts that are against them. One of these is [1], whose authors claim that “interaction is not enough” to ensure efficient simulation of face-to-face contact. However, the Canadian academic community (for instance, the Centre for Distance Education at Athabasca University) is a strong advocate of online conferences (see [2,3]). Among other advantages, this kind of conference is “family-friendly,” i.e., they break barriers for researchers with family obligations [4], in particular many women [5]. In addition, these conferences overcome the drawback of parallel sessions at face-to-face conferences, at which participants must choose certain talks and miss others. Anderson and Anderson [6] even put forward environmental and economic arguments: “Transportation is a major contributor of carbon dioxide (CO2) emissions.” On the other hand, Abdullah [7] and Kear, Chetwynd, and Jefferis [8] look at the matter from another point of view that is also important: Social presence at online conferences

Preyssler Heteropolyacids in the Self-Etherification of 5-Hydroxymethylfurfural to 5,5′-[Oxybis(methylene)]bis-2-furfural Under Mild Reaction Conditions

The synthesis of 5,5′-[oxybis(methylene)]bis-2-furfural (OBMF) from 5-hydroxymethylfurfural (5-HMF) was studied using bulk and alumina-supported Preyssler heteropolyacids (HPAs). The formation of OBMF was related to the amount of Brønsted acid sites, and the lowest yield of OBMF was obtained with supported HPAs. However, the Lewis acidity of the HPA supported on Al2O3 favored the formation of 2,5-dimethylfurane. The effects of solvent, catalyst loading, temperature, and reaction time on the selectivity to OBMF from 5-HMF were studied to optimize OBMF production using bulk Preyssler HPAs; a yield of 84 % to OBMF was obtained at 5 h and 343 K. These results demonstrate that bulk Preyssler HPA is a good candidate for OBMF synthesis under mild reaction conditions.Fil: Páez, Alexander. Universidad Pedagógica y Tecnológica de Colombia; ColombiaFil: Rojas, Hugo A.. Universidad Pedagógica y Tecnológica de Colombia;Fil: Portilla Zúñiga, Omar Miguel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas ; ArgentinaFil: Sathicq, Angel Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas ; ArgentinaFil: Afonso, Carlos A. M.. Universidade de Lisboa; PortugalFil: Romanelli, Gustavo Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas ; ArgentinaFil: Martínez, José J.. Universidad Pedagógica y Tecnológica de Colombia; Colombi

Incorporating Public Insecurity Indicators: A New Approach to Measuring Social Welfare in Mexico

Social Welfare (SW) is a multidimensional and contextual concept. It is generally adjusted to reflect the prevailing social realities of a given context (Grasso & Canova, 2008). It consists of a material dimension, including economic indicators such as income, employment, level of schooling, and access to social security services (Di Pasquale, 2008; Mæstad & Norheim, 2012). The other dimension of social welfare is subjective and includes elements such as happiness and satisfaction with life (Diener, 1994, 2000).ITESO, A.C.Boston College, School of Social WorkUniversidad Iberoamericana Ciudad de Méxic

A microstructural approach to modelling inelastic effects in fibred biological tissues

Enormous progress has been made during recent years in the phenomenological modelling of soft tissue. In general, three important softening phenomena associated with biological tissues may be distinguished. First, there is the dependence of the mechanical response on the previously attained maximum load level. This is quite similar to the well-known Mullins effect in rubber-like materials. Another typical phenomenon known as permanent set is characterized by residual strains after unloading. Finally, there is the softening behaviour resulting from fibre rupture and matrix disruption associated with material damage. There are several phenomenological constitutive models able to describe the failure of soft tissues from a macroscopic point of view. In this contribution a three-dimensional micro-sphere-based constitutive model for anisotropic fibrous soft biological tissue is presented, including elastic anisotropy as well as inelastic effects (softening, preconditioning and damage). The link between micro-structural inelastic contribution of the collagen fibers and macroscopic response is achieved by means of computational homogenization, involving numerical integration over the surface of the unit sphere. In order to deal with the random distribution of the fibrils within the fiber, a von Mises probability function is incorporated, and the mechanical behavior of the fibrils is defined by an exponential-type model. The inelastic effects in soft biological tissues were modeled by internal variables that characterize the structural state of the material