127 research outputs found

    Role of cervids and wild boar on the presence of tick-borne encephalitis virus in Sweden

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    Roe deer have been historically considered the main large mammal host for Ixodes ricinus ticks and it has been related with the current distribution and prevalence of tick-borne encephalitis virus in Sweden, being the main arguments the roe deer population peak and a series of mild winters in the nineties. Nowadays, roe deer is again at levels similar to the seventies, but the virus incidence and ticks abundance are still increasing. The role that other large mammal species play on this could be important to understand the current situation. We analysed the presence or absence of tick-borne encephalitis virus antibodies on 259 individuals of fallow deer, moose, red deer, roe deer and wild boar from blood samples collected by hunters during the hunting seasons of 2010 to 2013 in 31 municipalities. The results show infection in individuals of the five species, with the highest prevalence in roe deer, followed by moose, red deer, wild boar and fallow deer. However, the differences among the species are not significant. We also found that the age and sex of the individuals affect the probability of infection. This study demonstrates that not only roe deer, but the other four species analysed are important hosts for tick-borne encephalitis virus and they should be taken into account in the management of the wild populations to prevent an increase of the human infections

    Dinámica del hábitat larval e interacción ecológica de Aedes aegypti y Aedes albopictus en ambientes antrópicos de Panamá

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    Las especies de mosquitos Aedes aegypti y Aedes albopictus son importantes vectores de virus. Aunque su historia en la República de Panamá ha sido muy distinta, ambas especies se encuentra hoy en día presentes y ampliamente distribuidas en el territorio nacional. Ambas especies tienen preferencias de hábitat larvario muy similares, y pueden llegar a coocurrir en los mismos sitios de cría, habitualmente llantas usadas, tanques plásticos de agua, y otros recipientes de origen antrópico capaces de acumular agua. Para entender la relación de estas especies en su estado larval con los hábitats que ocupan, así como para conocer sobre posibles patrones de competencia, en 2016 y 2017 se llevó a cabo un extenso muestreo a lo largo y ancho del país en el que se recolectaron estadíos inmaduros de sitios de cría en residencias familiares y talleres de llantas usadas, tomando medidas de Temperatura y pH del agua para relacionar la presencia o ausencia de estas especies a las variables físico-químicas. Así mismo, se estudió la composición de la comunidad microbiana presente en estas especies con el objetivo de encontrar patrones que expliquen la distribución de Aedes aegypti y Aedes albopictus. Aedes aegypti no se vio afectada por la variación de temperatura y pH estudiados. Aedes albo-pictus, sin embargo, parece mostrar una mayor afinidad por temperaturas menores que Aedes aegypii, lo que tiene sentido dado su origen en latitudes templadas del planeta. La diversidad microbiana fue mayor en Aedes aegypti que en Aedes albopictus. Wolbachia fue encontrada en ambas especies y en distintas regiones del país distantes entre sí, lo que hace de este trabajo el primer reporte de Wolbachia en poblaciones salvajes de Aedes aegypti. Por otro lado, con el objetivo de estudiar el papel que juegan los talleres de llantas usadas en la distribución y dispersión de Aedes aegypti y Aedes albopictus, se muestrearon mediante ovi-trampas y búsqueda activa un total de 101 talleres a lo largo de las principales vías de circulación del país. Alrededor del 81% de los talleres muestreados fueron positivos para huevos de Aedes, un porcentaje elevado y representativo de la situación actual. De los 69 talleres donde se consiguió información a nivel de especie, Aedes aegypti apareció en 44 y Aedes albopiclus en 48. Un análisis de co-ocurrencia índica que las especies se encuentran en exclusión competitiva. La distribución espacial de las especies es heterogénea, lo que parece indicar que la predominancia de una especie en un territorio con respecto a la otra está condicionada por otros factores más allá de su efectividad para criarse y viajar en llantas

    The role of cervids and wild boar in the prevalence of tick-borne encephalitis in Sweden

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    Master i anvendt økologi. Evenstad 2014Roe deer have been historically considered the main large mammal host for Ixodes ricinus ticks and its population levels have been related to the current distribution and prevalence of tick-borne encephalitis virus (TBEv) in Sweden. It was thought that the increases in this disease were due to the roe deer population peak and a series of mild winters in the nineties. The roe deer is now at levels similar to the seventies, but the incidence of both TBEv and ticks are increasing. The role Swedish Association for Hunting and Wildlife Management, 2013 that other large mammal species play on this could be important to understand the current situation. We analysed the presence or absence of tick-borne encephalitis virus antibodies on blood samples from 259 individuals of fallow deer, moose, red deer, roe deer and wild boar from blood samples collected by hunters during the hunting seasons of 2010 to 2013 in 31 municipalities in south-central and southern Sweden. We found antibodies for tick-borne encephalitis in all five species, with the highest prevalence in roe deer (50% of positives), followed by moose (42%), red deer (42%), wild boar (32%) and fallow deer (25%). The prevalence was not significantly different between the species. However, age and sex significantly affected the probability of infection. This study demonstrates that not only roe deer, but the other four species analysed are important hosts for tick-borne encephalitis virus. The increase of these populations may cause an increase of Ixodes ricinus population and the incidence of TBEv, and they should be taken into account in the management of the wild populations to prevent an increase in human infections

    Análisis de las relaciones de los agentes sociales que operan en Residencias de personas mayores de la Región de Murcia

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    El envejecimiento poblacional es una realidad palpable y fácilmente observable. Si bien es cierto que el ritmo de envejecimiento poblacional es diverso en todo el planeta, en pocos años el segmento de los mayores de 65 años habrá alcanzado tasas nunca vistas antes en la historia del ser humano. Dentro de los diferentes dispositivos asistenciales de personas mayores aquel ubicado en las residencias cobra gran interés, a pesar de no ser muy extenso. Probablemente la escasez de bibliografía monográfica al respecto sea la causa de que hayan tantas aproximaciones conceptuales en torno del mundo residencial. El propósito de esta investigación ha sido la de analizar las relaciones de los agentes sociales que comprenden una residencia de ancianos en el contexto geográfico de la Región de Murcia. Estos agentes son los propios ancianos, sus familiares, los trabajadores de la residencia y los miembros de la organización que la conforma. Especial interés ha ocupado la naturaleza no lucrativa de las residencias estudiadas por la carga moralizante que estas expresan, a diferencia de las del sector público y las del sector empresarial mercantil. Siguiendo una metodología cualitativa, una etnografía, se han realizado 45 entrevistas semiestructuradas en 9 residencias de diversa forma administrativa (asociaciones, fundaciones y congregaciones religiosas). El trabajo de campo ha durado más de dos años con hallazgos muy interesantes. En el apartado de resultados y discusión han resaltado las apreciaciones acerca del propio concepto de residencia, el cual se ve impregnado de un halo de utilitarismo no tanto social como sanitario; así, para los ancianos que residen en estos centros el cariño y en buen trato son un gran objetivo a cubrir, mientras que la satisfacción de necesidades sanitarias queda en el terreno de los objetivos a conseguir por los familiares. Además, se ha observado especiales hallazgos en torno al término adaptación, el cual es utilizado indistintamente por pocos autores e incluso por la propia normativa legal, quedando puesto en duda su verdadero significado desde una perspectiva antropológica. Un aspecto importante de este trabajo de investigación ha sido la aprehensión de nuevos roles en la significación de la dinámica social diaria de la residencia, al menos entre los ancianos-residentes. Como marcas de estatus hemos podido constatar que el nivel cultural general, el nivel de estudios, la situación económica inmediata y el nivel de dependencia funcional van a situar a los ancianos que viven en las residencias estudiadas en un estrato más o menos alto o bajo respeto al resto. Como conclusiones podemos hemos podido destacar que el nivel de dependencia funcional y el cognitivo van a condicionar la forma de vida de todos los ancianos en la residencia. La residencia se ve trasformada por la demandas sociales pero en materia sanitaria, más que en la esfera social, lo cual pone hoy en día en entredicho la utilidad social de las mismas. El antiguo modelo de institución total impreso por Erving Goffmann como paradigma comparativo ha quedado desautorizado para tal fin ya que sus presupuestos teóricos son inaplicables a la realidad de las residencias estudiadas.Arte y HumanidadesCiencias Religiosa

    Developing a labelled object-relational constraint database architecture for the projection operator

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    Current relational databases have been developed in order to improve the handling of stored data, however, there are some types of information that have to be analysed for which no suitable tools are available. These new types of data can be represented and treated as constraints, allowing a set of data to be represented through equations, inequations and Boolean combinations of both. To this end, constraint databases were defined and some prototypes were developed. Since there are aspects that can be improved, we propose a new architecture called labelled object-relational constraint database (LORCDB). This provides more expressiveness, since the database is adapted in order to support more types of data, instead of the data having to be adapted to the database. In this paper, the projection operator of SQL is extended so that it works with linear and polynomial constraints and variables of constraints. In order to optimize query evaluation efficiency, some strategies and algorithms have been used to obtain an efficient query plan. Most work on constraint databases uses spatiotemporal data as case studies. However, this paper proposes model-based diagnosis since it is a highly potential research area, and model-based diagnosis permits more complicated queries than spatiotemporal examples. Our architecture permits the queries over constraints to be defined over different sets of variables by using symbolic substitution and elimination of variables.Ministerio de Ciencia y Tecnología DPI2006-15476-C02-0

    NMUS: Structural Analysis for Improving the Derivation of All MUSes in Overconstrained Numeric CSPs

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    Models are used in science and engineering for experimentation, analysis, model-based diagnosis, design and planning/sheduling applications. Many of these models are overconstrained Numeric Constraint Satisfaction Problems (NCSP), where the numeric constraints could have linear or polynomial relations. In practical scenarios, it is very useful to know which parts of the overconstrained NCSP instances cause the unsolvability. Although there are algorithms to find all optimal solutions for this problem, they are computationally expensive, and hence may not be applicable to large and real-world problems. Our objective is to improve the performance of these algorithms for numeric domains using structural analysis. We provide experimental results showing that the use of the different strategies proposed leads to a substantially improved performance and it facilitates the application of solving larger and more realistic problems.Ministerio de Educación y Ciencia DIP2006-15476-C02-0

    Distributed Model-Based Diagnosis using Object-Relational Constraint Databases

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    This work presents a proposal to diagnose distributed systems utilizing model-based diagnosis using distributed databases. In order to improve aspects as versatility, persistence, easy composition and efficiency in the diagnosis process we use an Object Relational Constraint Database (ORCDB). Thereby we define a distributed architecture to store the behaviour of components as constraints in a relational database to diagnose a distributed system. This work proposes an algorithm to detect which components fail when their information is distributed in several databases, and all the information is not available in a global way. It is also offered a proposal to define, in execution time, the allocation of the sensors in a distributed system.Ministerio de Ciencia y Tecnología DPI2003-07146-C02-0

    Applying Constraint Databases in the Determination of Potential Minimal Conflicts to Polynomial Model-Based Diagnosis

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    Model-based Diagnosis allows the identification of the parts which fail in a system. The models are based on the knowledge of the system to diagnose, and may be represented by constraints associated to the components. The variables of these constraints can be observable or non-observable, depending on the situation of the sensors. In order to obtain the potential minimal diagnosis in a system, an important issue is related to finding out the potential minimal conflicts in an efficient way. We consider that Constraint Databases represent an excellent option in order to solve this problem in complex systems. In this work we have used a novel logical architecture of Constraint Databases which has allowed obtaining these potential conflicts by means of the corresponding queries. Moreover, we have considered Gröbner Bases as a projection operator to obtain the potential minimal conflicts of a system. The first results obtained on this work, which are shown in a heat exchangers example, have been very promising.Ministerio de Ciencia y Tecnología DPI2003-07146-C02-0

    Querying a Polynomial Object-Relational Constraint Database in Model-Based Diagnosis

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    Many papers related to Constraint Databases (CDBs) theories exist, including proposals that present frameworks for the treatment of constraints as a new data type. Our proposal presents a new way of storing and manipulating constraints as a usual data, and of making queries about the constraint variables derived from an Object-Relational Constraint Database (ORCDB). In this work, the constraints stored in an ORCDB are only polynomial equality constraints. The proposal is based on Gr¨obner bases, constraint consistency and constraint optimisation techniques. Most works in CDB use spatial-temporal data as a case study, however this work presents an emergent engineering domain, that of fault diagnosis.Ministerio de Ciencia y Tecnología DPI2003-07146-C02-0

    Improving the determination of minimal hitting sets in model-based diagnosis using constraint databases

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    In model-based diagnosis, minimal hitting sets are usually used to identify which components may fail in a system. This work presents a set of algorithms to improve the determination of all Minimal Hitting Sets. Our proposal uses the minimal conflict sets to obtain, in an efficient way, the diagnosis of a system. The improvement consists of three algorithms which analyse only the relevant options. This proposal builds an equivalent system in order to obtain all minimal hitting sets depending on the location of the sensors. At the same time, all the information of the process is stored in a Constraint Database, keeping the information persistent and recoverable. Some empirical results are presented in order to show how the proposal improves the process in order to obtain all minimal hitting sets.Ministerio de Ciencia y Tecnología DPI2003-07146-C02-0
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